feat(omp): survive a full session kill by reading omp's own transcripts

Claude conversations survive "Kill Tmux & Claude" because Codeman reads
them back independently from ~/.claude/projects, not from its own
session bookkeeping. omp conversations had no equivalent: kill the
Codeman session and the conversation vanished from Past Sessions
entirely, even though omp itself never forgot it on disk.

Adds omp-transcript.ts, a scanner over omp's own
~/.omp/agent/sessions/<mangled-cwd>/<uuid>.jsonl files (the same shape
as Claude Code's own transcript scanner, but simpler -- these files are
small enough to read whole instead of doing head/tail windows). Each
file's own "session" header line carries the real cwd and session id
directly, so unlike Claude's mangled-directory-name decoding this
never has to guess. Wired into gatherUnifiedInputs() as a second
history source alongside the Claude scan, and HistoryInput/
mergeUnifiedSessions() now carry an optional `mode` so a non-claude
history-only row still gets a real mode badge.

Also fixes the ambiguity behind the "continue picks the wrong
conversation" report from this session's testing: omp mints its OWN
session uuid, unrelated to Codeman's, so a live/persisted row and its
own history-scan row would otherwise show up as two separate entries
for the same conversation the moment the id gets resolved. Reuses the
existing claudeSessionId alias field (mergeUnifiedSessions' fold-into-
owner mechanism) to point at the resolved omp id, threading it through
every place `_claudeSessionId` gets (re)computed -- the constructor,
_resolvedOmpRespawnConfig, and a new _maybeCaptureOmpSessionId() that
opportunistically resolves it the first time a brand-new omp session
(one that has never gone through a respawn) goes idle.

Also closes a THIRD instance of the "ompConfig never got wired in
here" gap this session kept finding: restoreMuxSessions() in server.ts
restores every sibling CLI's config from persisted state on boot except
omp's, so a boot-recovered omp session always lost its resolved resume
id and fell back to guessing again.

Verified live end-to-end: told a session a secret, killed it fully
(Kill Tmux equivalent, killMux=true -- the Codeman session AND its tmux
pane both gone), and the conversation still showed up in the unified
list as a history-sourced row with the real first prompt as its title
and an omp mode badge, keyed by omp's own session id.

Known remaining gap, not fixed here: the claudeSessionId alias doesn't
yet resolve reliably on every boot-recovery path for a session that
was never respawned while alive (e.g. a plain re-attach to a pane that
was never dead) -- worth a follow-up, but doesn't affect the two things
that matter most: the conversation surviving a kill, and continuation
correctness once an id has been resolved (which happens on the very
next respawn either way).

src/web/server.ts

@@ -2755,6 +2755,7 @@ export class WebServer extends EventEmitter {
               piConfig: muxSession.mode === 'pi' ? savedState?.piConfig : undefined,
               grokConfig: muxSession.mode === 'grok' ? savedState?.grokConfig : undefined,
               deepSeekConfig: muxSession.mode === 'deepseek' ? savedState?.deepSeekConfig : undefined,
+              ompConfig: muxSession.mode === 'omp' ? savedState?.ompConfig : undefined,
               envOverrides: savedEnvOverrides,
               effort: savedState?.effort,
               attachmentHistory: savedAttachmentHistory,