feat(i18n): key translation pairing records by heading section (#5036)

* feat(i18n): key translation pairing records by heading section

Replace the whole-file blob hashes in *.i18n.yaml with one entry per
heading section that still holds language-specific content, keyed by the
English heading-slug path. Blocks identical across the pair (generated
table rows, code blocks, shared regions) stay out of the hash, so edits to
different sections and identical regenerations merge with Git's default
text merge, including on GitHub.

Remove the dsh-translation-pairing merge driver, its resolver command and
installer wiring; gen-translation-brief recovers last-confirmed text from
commit history. Migrate all active records, archive the superseded Agent
Note, and record the replayed conflict reduction in the new one.

* test(i18n): refresh translation prompt snapshot for the terminology note

* feat(i18n): exclude only code blocks and generated regions from pairing records

Replace byte-equality masking with an explicit rule: a record hash skips
fenced code blocks and BEGIN/END GENERATED regions, the two kinds of
content the pairing gate already requires to be identical on both sides.

Move generated data into regions written into both pages:
gen-config-catalog renders both languages and the record with per-package
regions labelled by code identifiers; gen-module-graph keeps its table in a
region; gen-doc-graphs splices the event matrix regions into the Chinese
page. Add a generic region splice beside the region grammar.

SAFETY.i18n.yaml

@@ -1,6 +1,19 @@
-# Bilingual-pair consistency record (docs/i18n/README.md): the git blob hash of each
-# side as of the last confirmed-consistent state. Both languages carry equal authority;
-# after editing either side, bring the other along and re-record with:
+# Bilingual-pair consistency record for SAFETY.md (docs/i18n/README.md): per heading
+# section, a hash of its English and Chinese blocks outside code blocks and generated regions.
+# After editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write SAFETY.md
-SAFETY.md: 2b76f00e0619ee69553afdc507df361080f4d3ac
-SAFETY.zh.md: 6f7dae47b3e47ddfb155adb9c8c868b516d75360
+/safety:
+  en: a374f70c56b3f221
+  zh: a07f7a9ba9af40fc
+/safety/experimental-status:
+  en: 39a995a6c819f73e
+  zh: e577df19392736ac
+/safety/sandbox-limitations:
+  en: a2b6cf1311f3abb6
+  zh: c3694663312f4d6c
+/safety/responsible-use:
+  en: ca3e9da7c0b360fe
+  zh: c0a6891a197d48cd
+/safety/no-warranty-or-liability:
+  en: 71a2989f530f2018
+  zh: e90e55f11068a91f