Fix DocC path renaming to preserve doc:// identifiers

[paduh]

Motivation

• Avoid corrupting DocC doc:// identifiers caused by blanket colon-to-hyphen rewrites in generated JSON/HTML.
• Ensure artifact upload compatibility by renaming only actual files/dirs that contain colons rather than globally rewriting colons.
• Keep local test script behavior aligned with the CI workflow to reduce divergence and surprises.

Description

• Replace global JSON/HTML colon-rewrite logic with a targeted rename map built by build_rename_map and applied by apply_renames in ./.github/workflows/docs.yml.
• Only update references that correspond to renamed paths via build_replacements and replace_all, removing the previous blanket JSON/regex rewriting that affected doc:// values.
• Mirror the workflow changes in test-docs.sh by adding the same Python-based rename-and-replace implementation for ./docs-test.
• Files modified: /.github/workflows/docs.yml and test-docs.sh.

Testing

• No automated tests were executed as part of this change.
• Changes were committed and staged locally (git commit succeeded) but no CI run was performed here.
• Basic runtime behavior was preserved by keeping the rename ordering depth-first to avoid path conflicts during rename operations.
• The scripts print summary counts of renamed paths and updated files for runtime verification.

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Codex Task