fix(dashboard): fetch transcript by exact meeting row (hotfix on the deployed base)

[DmitriyG228]

Closes #1386.

The meeting page fetched the transcript by platform/native_meeting_id, which resolves the newest row for that native id. For a recurring meeting, calendar auto-join creates the next occurrence's scheduled row minutes after a call ends, and the completed meeting's page then rendered that empty newer row (prod 27493 → 27499, 271 segments hidden).

When the internal id is known, fetch /transcripts/by-id/{id} (owner-scoped, live in prod meeting-api + gateway). Falls back to the native route otherwise. Cherry-pick of eecd9acf (July 23) onto fa667cd1, the commit prod's dashboard image is built from — deliberately not onto this branch's head, so the shipped image carries only this change. Two vitest cases.

Rung: image built from this commit (org.opencontainers.image.revision label); prod delivery via channel entry seq-13, adoption in Vexa-ai/vexa-platform#392.

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[github-actions]

🃏 Merge card — #1387

check		what it needs
Value	❌	missing state: value-signed (the value sign-off)
Diff	✅	maintainer self-review — @DmitriyG228 holds the commit bit (no separate non-author review required)

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