#21276: fix(telegram): stabilize partial finalization and MEDIA dedupe (AI-assisted)

## Summary - Problem: Telegram `streamMode: partial` finalization could regress/overwrite expected final behavior, and MEDIA path variants (e.g. `file://` vs local path) could be treated as different entries. - Why it matters: Users can see unstable final message behavior and duplicate/incorrect media handling in Telegram. - What changed: Stabilized partial-to-final ordering in Telegram draft flow, normalized MEDIA path variants for dedupe, and added/updated focused tests. - What did NOT change (scope boundary): No provider/model behavior changes outside Telegram/media payload handling. ## Change Type (select all) - [x] Bug fix - [ ] Feature - [ ] Refactor - [ ] Docs - [ ] Security hardening - [ ] Chore/infra ## Scope (select all touched areas) - [ ] Gateway / orchestration - [ ] Skills / tool execution - [ ] Auth / tokens - [ ] Memory / storage - [x] Integrations - [ ] API / contracts - [ ] UI / DX - [ ] CI/CD / infra ## Linked Issue/PR - Closes #18780 - Related #18784 ## User-visible / Behavior Changes - Telegram partial streaming finalization is more stable and less likely to regress at finalization boundary. - MEDIA path variants (`file://...` vs equivalent local path) are deduped consistently. ## Security Impact (required) - New permissions/capabilities? (`No`) - Secrets/tokens handling changed? (`No`) - New/changed network calls? (`No`) - Command/tool execution surface changed? (`No`) - Data access scope changed? (`No`) - If any `Yes`, explain risk + mitigation: `N/A` ## Repro + Verification ### Environment - OS: macOS (local dev) - Runtime/container: Node.js + pnpm - Model/provider: N/A (unit tests) - Integration/channel (if any): Telegram - Relevant config (redacted): standard local config; no new config required ### Steps 1. Run Telegram partial-stream test paths and MEDIA payload dedupe tests. 2. Compare behavior for partial/final ordering and path-variant dedupe. 3. Confirm no regressions in targeted suites. ### Expected - Stable finalization ordering in partial stream mode. - Equivalent MEDIA paths dedupe to one logical entry. ### Actual - Verified via passing targeted tests after patch. ## Evidence - [x] Failing test/log before + passing after - [ ] Trace/log snippets - [ ] Screenshot/recording - [ ] Perf numbers (if relevant) ## Human Verification (required) - Verified scenarios: targeted Telegram draft-stream, dispatch, and payload dedupe tests. - Edge cases checked: regressive partial snapshots, file/path variant dedupe. - What you did **not** verify: full live Telegram E2E against production bot. ## Compatibility / Migration - Backward compatible? (`Yes`) - Config/env changes? (`No`) - Migration needed? (`No`) - If yes, exact upgrade steps: `N/A` ## Failure Recovery (if this breaks) - How to disable/revert this change quickly: revert this PR commits. - Files/config to restore: Telegram draft/payload files touched in this PR. - Known bad symptoms reviewers should watch for: duplicate media outputs or partial/final ordering regressions. ## Risks and Mitigations - Risk: Over-dedup in unusual path edge cases. - Mitigation: path-variant tests added/updated; scope limited to MEDIA dedupe logic. <!-- greptile_comment --> <h3>Greptile Summary</h3> Stabilizes Telegram partial finalization ordering and normalizes MEDIA path variants for deduplication. The changes address two key issues: (1) partial-to-final message ordering regressions, and (2) `file://` vs local path variants being treated as different media entries. **Key changes:** - Added `normalizeMediaForDedupe` function in `reply-payloads.ts` that strips `file://` prefix to normalize path variants for consistent deduplication - Added tests for cross-variant MEDIA deduplication (`file:///tmp/photo.jpg` vs `/tmp/photo.jpg`) - Added test coverage for draft stream finalization edge cases (message ID available after stop) - Added tests for partial mode behavior (no force new message on assistant restart or reasoning end) **Issues found:** - Two duplicate test names in `bot-message-dispatch.test.ts` that will cause test framework issues (lines 418 and 504) <h3>Confidence Score: 3/5</h3> - safe to merge after fixing duplicate test names - core logic changes are focused and well-tested, but duplicate test names will cause test execution issues that must be resolved before merge - src/telegram/bot-message-dispatch.test.ts requires removing duplicate tests before merge _{Last reviewed commit: 5ac94b4} <!-- greptile_other_comments_section --> <!-- /greptile_comment -->