Draft: Visibility sync since v1.3.0 (existing PRs + Enveritas fixes/features)

[MerlinVeritas]

Summary

This PR is a visibility-only sync of changes made since v1.3.0.
It mostly bundles a few already-existing PRs, plus a small set of Enveritas-specific features/fixes we needed
in production.

This is not intended as a polished upstream proposal yet; we can refine/split/reword once there is interest
in including parts of this upstream.

What’s included (since v1.3.0)

• Existing upstream/community work already in forks:
  • feat: add overrides config option enveritas/sqlc-gen-python#2 feat: add overrides config option
  • Invalid name generation when using python reserved keywords enveritas/sqlc-gen-python#4 Escape-Technologies-main merge (includes related fixes/tests)
• Enveritas additions/fixes:
  • Fix/escape constants enveritas/sqlc-gen-python#5 escape constants / keyword and docstring cleanup
  • Fix/struct format enveritas/sqlc-gen-python#6 struct/param/return type formatting fixes (CamelCase, ReplaceAll)
  • Fix/support enum enveritas/sqlc-gen-python#7 enum generation fixes + schema-prefix enum type option
  • Support type overrides in addition to column overrides enveritas/sqlc-gen-python#8 type overrides support + stricter YAML validation + CI/test updates

Why this PR

• Provide maintainers visibility into what can potentially be included upstream.
• Serve as a staging PR that can be polished and split into upstream-friendly pieces if there’s interest.

Notes

• Scope here is intentionally broad and mostly aggregative.
• Happy to follow up with:
  1. smaller focused PRs,
  2. cleanup of commit history/messages,
  3. docs/config examples aligned to upstream conventions.