Document and complete stale branch triage

plan.md

@@ -515,10 +515,42 @@ Status: validated and merged into the integration branch by child pull request [
 
 ### Child Execution Record: [#216](https://github.com/WordPress/try-wordpress/pull/216)
 
-Status: implemented and validated locally in child pull request [#216](https://github.com/WordPress/try-wordpress/pull/216), which targets the integration branch.
+Status: validated and merged into the integration branch by child pull request [#216](https://github.com/WordPress/try-wordpress/pull/216) at merge commit `f8473294df0b45bc0afa10e580f238068063c24d`.
 
 - Composer metadata: the root description now accurately identifies Try WordPress as a browser extension for importing an existing website into WordPress. The existing empty Composer license value is byte-semantically unchanged, and no other Composer declaration or lock entry changes.
 - npm metadata: the private root package now declares repository-grounded name `try-wordpress`, plugin-header version `0.0.1`, and `private: true`; the existing Node engine range `>=24 <25`, scripts, and dependency declarations remain unchanged. npm 11 synchronizes the same name and version into the package-lock top level and root package, while exact semantic comparison after excluding only those identity fields proves every inherited lock entry unchanged.
 - Backup ignores: `.gitignore` adds exactly `/backup.sql` and `/backup-*.sql`, matching the two root files emitted by `composer run dev:db` and `composer run dev:db:backup`; nested backup SQL files and unrelated SQL files remain trackable.
 - Scope: `LICENSE`, plugin and extension metadata, license metadata, dependencies, resolved versions, integrity values, scripts, application source, and CI workflows are unchanged.
 - Validation: Node `v24.18.0` with npm `11.16.0` parses both npm JSON files and reproduces the inherited audit result of 111 effects (9 low, 15 moderate, 87 high, and zero critical) across 60 unique GHSAs. Exact lock, metadata, engine, script, dependency, license, and ignore-behavior assertions pass. The official Composer 2 container validates `composer.json` and reports only the inherited warnings for the intentionally unchanged empty license field; `composer audit --locked --no-interaction` reports no advisory. The approved-plan-prefix SHA-256 remains `6c29481eab5ef6c57aec974295193492861bc7efeba1bd612e45c94d10b1bfaa`, the baseline table remains exactly 124 rows, and `git diff --check` passes.
+
+### Child Execution Record: [#217](https://github.com/WordPress/try-wordpress/pull/217)
+
+Status: pre-action evidence was captured and linked in child pull request [#217](https://github.com/WordPress/try-wordpress/pull/217), which targets the integration branch, before the authorized external branch deletion completed.
+
+- Approved criterion: a live remote branch is eligible for deletion only when it has an associated pull request in any state or its exact tip is reachable from `origin/trunk`; an unmerged branch without an associated pull request must be preserved.
+- Reachability anchor: local `origin/trunk` is exactly `98f7c74d195d0b1ee95e4f9c16c7a9b527149980`, matching the approved pre-action anchor.
+- Live-source scope: the paginated GitHub branches API contains thirteen of the fourteen original stale branches and omits `crawler`; the complete all-state pull-request response supplies every same-repository head association shown below.
+
+| Branch | Live API state | Exact pre-action tip or recovery SHA | Last commit date | Reachable from `origin/trunk` | All associated head PRs / state | Criterion result | Recovery reference |
+| --- | --- | --- | --- | --- | --- | --- | --- |
+| `add-navigation` | Present | `55fbcd77ed9f6bcd3bf9528c9898816b02be29ba` | `2024-11-07T17:04:03+01:00` | No | [#98](https://github.com/WordPress/try-wordpress/pull/98), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #98. |
+| `api-docs` | Present | `d6af87dd5891f64539d5dfde819fa2d563095caf` | `2024-10-25T15:34:17+01:00` | No | [#86](https://github.com/WordPress/try-wordpress/pull/86), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #86. |
+| `attempt-twitter` | Present | `09ea6328c0a7553328b1dddf78a2b35958e2fa15` | `2024-08-01T13:25:16+02:00` | No | None found | Preserve because the tip is unmerged and no associated PR exists. | Live remote branch and tip SHA. |
+| `crawler` | Absent before child 018 | `ba0be4d3c71b5dfeeff71b9e5d81789cdc0ab27a` | `2024-12-02T12:50:08+04:00` | No | [#131](https://github.com/WordPress/try-wordpress/pull/131), closed (unmerged) | No-op because the remote branch was already absent; this child did not delete it. | Recovery commit SHA, PR #131, and the original baseline inventory. |
+| `devex` | Present | `1f10e37b8b698965abdb3a2c2d7db9d40defa003` | `2024-11-19T16:21:02+04:00` | No | [#123](https://github.com/WordPress/try-wordpress/pull/123), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #123. |
+| `docs/extend` | Present | `361343c169e69bca2357bb4a25d9225f9a774109` | `2024-12-04T18:28:39+04:00` | No | [#125](https://github.com/WordPress/try-wordpress/pull/125), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #125. |
+| `docs-definitions` | Present | `343cbb6e8ab61ed5b6a910ca87b50a1af89e41ed` | `2024-11-22T15:24:36+01:00` | No | [#124](https://github.com/WordPress/try-wordpress/pull/124), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #124. |
+| `feedback_auto_preview_filter` | Present | `0d3ca5c76aec03956f561161376631f334ddbedc` | `2024-11-26T01:10:02+04:00` | No | [#128](https://github.com/WordPress/try-wordpress/pull/128), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #128. |
+| `feedback_simulate_liberation` | Present | `1899e033db7ecf42aeb005aec3dd0c00ca89e55d` | `2024-11-25T19:37:15+04:00` | No | [#126](https://github.com/WordPress/try-wordpress/pull/126), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #126. |
+| `fix-test-wix` | Present | `960f2d793bdf975e39c31304a296c168c0301aff` | `2024-11-12T15:09:21+01:00` | No | None found | Preserve because the tip is unmerged and no associated PR exists. | Live remote branch and tip SHA. |
+| `local-playground-client` | Present | `2a34ea44ea3ae8d8abb0c9365a866cbdc65338b5` | `2024-07-24T10:41:15+02:00` | Yes | None found | Deleted externally after PR #217 opened; eligibility was exact tip reachability from `origin/trunk`. | Tip SHA and `origin/trunk`, which contains it. |
+| `npm_package_updates` | Present | `c9070d9d1bdd66ccf7a374d463b45c99e14e7683` | `2024-09-11T21:19:31+04:00` | No | None found | Preserve because the tip is unmerged and no associated PR exists. | Live remote branch and tip SHA. |
+| `pages` | Present | `b1ed8fa5872402690a3a7286742337526d42dd10` | `2024-11-07T15:54:07+01:00` | No | [#96](https://github.com/WordPress/try-wordpress/pull/96), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #96. |
+| `schemas` | Present | `85e269198e8f0d2c9d6039af89e1cd5d0188003d` | `2024-12-03T15:19:15+00:00` | No | [#132](https://github.com/WordPress/try-wordpress/pull/132), closed (unmerged) | Deleted externally after PR #217 opened; eligibility was the associated PR. | Tip SHA and PR #132. |
+
+- Authoritative completed external deletion set: `add-navigation`, `api-docs`, `devex`, `docs/extend`, `docs-definitions`, `feedback_auto_preview_filter`, `feedback_simulate_liberation`, `local-playground-client`, `pages`, and `schemas`.
+- Authoritative preserve set: `attempt-twitter`, `fix-test-wix`, and `npm_package_updates`.
+- Authoritative no-op set: `crawler`, which remains absent and retains the documented recovery references.
+- External deletion result: after PR #217 opened and the pre-action evidence was immediately reverified, the main maintenance workflow deleted exactly the ten authorized remote branches and no others. Remote-head deletion is external to source history; every removed branch remains recoverable from its exact pre-action SHA and associated PR or reachable trunk reference listed above.
+- Post-action verification: both `git ls-remote --heads origin` and the paginated live branches API show all ten completed deletions absent, `crawler` still absent, and the preserved heads unchanged at `attempt-twitter` `09ea6328c0a7553328b1dddf78a2b35958e2fa15`, `fix-test-wix` `960f2d793bdf975e39c31304a296c168c0301aff`, and `npm_package_updates` `c9070d9d1bdd66ccf7a374d463b45c99e14e7683`. The active `trunk`, `agent/maintenance-security-and-hygiene`, and `agent/maintenance-018-stale-branch-triage` heads also remain present.
+- Validation: the live remote and API branch sets are identical at six exact heads; the approved-plan-prefix SHA-256, 124-row baseline-alert count, Markdown table structure, and `git diff --check` pass. This documentation update performs no additional GitHub mutation.