feat: wrap each locale and pot file in its own details section

[barredterra]

Split oversized sections across comments instead of truncating, and keep packing small sections together when they fit.

[greptile-apps]

Confidence Score: 5/5

Safe to merge; the refactor correctly replaces truncation with proper per-locale splitting and all new code paths are covered by tests.

The binary-search splitting logic is sound (monotonicity holds, conservative bounds prevent false fits, final sections are rebuilt with correct counts), packing is unchanged, and five new tests verify wrapping, packing, and splitting for both PO and POT paths. No dropped rows, no data loss, no silent truncation.

No files require special attention.

_{Reviews (2): Last reviewed commit: "fix: validate fast-path sections against..." | Re-trigger Greptile}