[production] Remove retired Amazon templates

[shrey150]

Summary

• remove the TypeScript and Python amazon-global-price-comparison templates from the production branch
• remove the TypeScript and Python amazon-product-scraping templates from the production branch
• remove both entries from the production README index

This is the production-branch counterpart to #105. Both current public branches contain the retired source directories, so both need cleanup; merging only the default-branch PR would leave the runnable source publicly reachable on production.

E2E Test Matrix

Command / flow	Observed output	Confidence / sufficiency
node scripts/check-readme-template-index.mjs	README template index matches 41 template rows covering 73 first-level template directories.	Proves the production directory tree and README index stay synchronized after the four directories are removed.
Repository-wide authored-source search for both retired slugs/names	Zero matches.	Confirms neither retired Amazon template remains advertised or implemented on the production branch.
Query live /api/templates for slugs containing amazon	Zero matching templates.	Confirms this branch cleanup agrees with the already-delisted public website/playground catalog.

Default-branch cleanup: #105

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Note

Low Risk
Documentation and sample-template deletion only; no runtime, auth, or shared infrastructure changes.

Overview
Removes the retired amazon-global-price-comparison and amazon-product-scraping templates (TypeScript and Python) from the production branch, and drops both rows from the README index.

This is the production counterpart to default-branch cleanup so the retired source is no longer publicly reachable on either branch.

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