fix(telegram): tolerate invalid bridge dates

[aiirvizionz]

Summary

• guard Telegram bridge message dates before converting them to ISO strings
• fall back to the Unix epoch for missing, non-finite, or out-of-range values
• add regression coverage for valid and invalid Bot API timestamps

Validation

• .\\node_modules\\.bin\\vitest.cmd run packages/bridges/telegram/src/index.test.ts
• .\\node_modules\\.bin\\tsc.cmd -p packages/bridges/telegram/tsconfig.json --noEmit
• git diff --check

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🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.