feat: ADR-0034 — history journal records err + replay parses/filters the journal

Replay (§3): run_replay parses <ts>|<status>|<source> journal records — runs ok, skips non-ok — while still accepting bare .commands scripts (prefix-detected so a | inside a bare command isn't misread). Fixes replay history.log, which died on line 1.

Journal failures (§1/§2): failed commands are recorded err via a new Action::JournalFailure, emitted by the pure-sync App for both parse failures and worker-execution failures (runtime appends best-effort, never fatal). Hydration reads all records so typo'd/rejected commands are recallable across sessions.

Amendment 1 — replay filters app-lifecycle commands: a working replay history.log exposed that the journal also records save as/load/new/export/import/rebuild/mode (which would panic the worker dispatch or abort replay). Replay now re-applies only schema/data writes and skips every app-lifecycle command + nested replay, classified by entry word so modal/incomplete forms (save as, bare mode) and quit skip uniformly rather than aborting. All skips continue (reversing the nested-replay refusal); import and nested replay warn. replay.error_nested removed; replay.skipped_import/_replay added; ReplayCompleted carries warnings. requirements.md U3/U4 updated; app-command runtime-failure journalling tracked as a follow-up.

1659 passing / 0 failing / 0 skipped / 1 ignored. Clippy clean.

src/action.rs

@@ -24,6 +24,17 @@ pub enum Action {
         command: Command,
         source: String,
     },
+    /// Record a *failed* submission to `history.log` as an `err`
+    /// record (ADR-0034 §1/§2). Emitted by the pure-sync `App`
+    /// for both failure kinds — a line that failed to parse (at
+    /// submit) and a command the worker rejected (on
+    /// `AppEvent::DslFailed`) — because the App does no I/O. The
+    /// runtime appends best-effort: a failure to record a failure
+    /// must never escalate a user error into a fatal (ADR-0034
+    /// §4). `source` is the original user-typed text.
+    JournalFailure {
+        source: String,
+    },
     /// User issued the `rebuild` app-level command (ADR-0015
     /// §7, §11). Runtime computes a summary from
     /// `project.yaml` + `data/` and posts back as