* feat(planguard): read sqlc statement text and load a strict plan corpus
* fix(planguard): fail on unextracted statements, keep fragments mode-neutral
* feat(planguard): plan assertions, scoped sort exemptions and narrow retired-index verdicts
* fix(planguard): an errored run always fails
* fix(planguard): keep subplan conds off their parent scan; fail on unanalyzed budgets
* feat(planguard): read-only plan runner, reports and the run command
* fix(planguard): validate identifiers in emitted scripts; prove read-only runs
* feat(planguard): end-state corpus, planted regressions and the generated cached-plan policy
* fix(planguard): derive observer cases from data; mark legacy generic plans
* fix(planguard): bound the dense-region route resolvers; test policy refusals
* fix(planguard): re-measure the dense-region route cases; cover every policy refusal
* feat(planguard): synthetic fixture built through the migrations, checked in CI
* ci(planguard): build the fixture once; guard fixture data for identifiers
* fix(planguard): hash every fixture generator input; harden the fixture guard
* feat(planguard): snapshot diff over every column, named result classes and cursor walks
* fix(planguard): bound the relaxed diff classes; derive the cursor tie from data
* fix(planguard): refuse multi-statement text in the corpus runner
* feat: read-only server mode and an HTTP page diff between two builds
* fix(planguard): refuse escape strings and psql meta-commands in corpus text
* fix: storediff follows each build's own cursor; prove read-only gates via the log
* fix(planguard): match the PostgreSQL lexer on high-bit bytes; check every emitted line
* feat(admin): daily read-only plan check on the maintenance pool, its metric and report
* feat(planguard): daily prod check behind planguard.daily_check
* fix(planguard): cancel fresh runs at shutdown; expose a never-ran check
* ci(planguard): pin the fixture server and collation; refresh baselines
* fix(planguard): calibrate route budgets on one dataset; skip entries whose index is absent
