fix(build): repair three type errors that break pnpm -r build

[hugoboss23-5]

pnpm -r build fails on master today. Three distinct type errors block the
workspace build at three different packages. This fixes all three.

1. packages/bots/core and packages/bot/core — TS2345

Both packages carry a duplicated copy of the same SessionManager. In each, the
local finish callback re-declares its parameter as an inline structural type
with widened primitives:

const finish = (result: {
  type: string;      // AIResult requires the literal "result"
  subtype: string;   // AIResult requires "success" | "error"
  ...
}) => { ... resolve(result); }

AIResult is declared a few lines above in the same file and requires string
literals. A widened string is not assignable to a literal type, so
resolve(result) is rejected.

Fixed by annotating the parameter with the existing AIResult interface rather
than restating its shape. That also deletes a hand-duplicated type which had
already drifted from its source — the drift is what allowed the mismatch, so
removing it prevents a recurrence.

2. packages/bots/signal — TS2322

The object literal in the timestamp-fallback test does not satisfy
IncomingMessage in three ways:

• groupId: undefined where the interface declares string | null
• required field isGroup missing
• excess property raw that is not on the interface

All three corrected, not just the one the compiler reports first. The test's
intent — an out-of-range timestamp falls back to epoch — is unchanged.

Verification

• tsc -p tsconfig.json --noEmit exits 0 for each affected package, using the
  repo's own pinned typescript@5.9.3 from the lockfile.
• vitest run packages/bots/signal → 7 passed (7).
• Full pnpm -r build now completes green through sites/sh1pt.com build: Done.

No runtime logic changed; the diff is entirely type-level, net -22/+4.

Note on what I deliberately did not include

While investigating I also saw TS2307 Cannot find module for
@profullstack/sh1pt-policy and @profullstack/sh1pt-action-packs in
packages/cli. Those are not bugs — both are real workspace packages
correctly declared workspace:^; the errors only appear when typecheck runs
before those packages are built. Building them first clears it. Excluded from
this PR.