doc: update startup-error names

doc/CHANGES/history/PLAN-startup-db-failure-recovery.md

@@ -3,7 +3,7 @@
 ## Status
 
 Closed without building Parts A–C. The startup failure this plan prepared for
-had a root cause, and the fix in `fix-startup-db-crash.md` removed it: the
+had a root cause, and the fix in `PLAN-startup-db-fix-crash.md` removed it: the
 SQLite plugin's configuration key, migration recording, and Android backup
 rules. A user who saw the error on every launch started normally after
 installing a build with that fix.
@@ -154,7 +154,7 @@ Parts A–C are deferred, not scheduled.
   error, the `startupError.ts` hand-off to `StartView`, and the recovery screen
   (Try Again, Email/Copy Details, Save a Copy, Start Over).
 - 2026-10-10: commit f41a807a fixed the root cause (see
-  `fix-startup-db-crash.md`) and wrote this plan. Tagged 1.4.8; the CHANGELOG
+  `PLAN-startup-db-fix-crash.md`) and wrote this plan. Tagged 1.4.8; the CHANGELOG
   records it under 1.4.9 as "Startup DB error for new installations".
 - 2026-10-17: commit d2cdd578 added the WebAssembly explanation to the recovery
   screen (CHANGELOG 1.4.10).