fix(line): map LINE msg_type to valid MessageType enum values

[x1001000]

Summary

• plugins/platforms/line/adapter.py:971 referenced MessageType.IMAGE, which does not exist on gateway.platforms.base.MessageType — every
  non-text inbound LINE message would have raised AttributeError at construction time.
• Replace the ternary with a line_to_message_type mapping that routes each LINE webhook msg_type to a real enum value: image→PHOTO,
  video→VIDEO, audio→VOICE (LINE audio is mic voice notes, so VOICE fires STT + auto-TTS reply per gateway/run.py:8393-8394),
  file→DOCUMENT, sticker→STICKER, location→LOCATION, with TEXT as the default.

Test plan

• Send a text message via LINE — handled as MessageType.TEXT.
• Send an image — handled as MessageType.PHOTO.
• Send a voice note (mic button) — handled as MessageType.VOICE, STT fires.
• Send a sticker / location — handled with correct enum and no exception.

[alt-glitch]

Duplicate of #34233 / #27142 (same root cause: LINE adapter references non-existent MessageType.IMAGE, breaking all non-text inbound messages with AttributeError; same fix mapping msg_type → valid enum values). Consolidating on the earliest canonical fix.

[mxnstrexgl]

🤖 Automated PR Review

Security Scan

• ✓ No hardcoded secrets, injection sinks, unsafe deserialization, or dependency red flags found by this automated scan.

Code Quality

• ✓ No blocking code-quality issues found by this automated scan.
• ℹ️ No test file changes detected; verify existing coverage exercises this behavior.

Summary

Status: APPROVE — security findings: 0, quality suggestions: 0.

Automated review; raw diff content intentionally omitted.

[tonydwb]

Code Review Summary

Verdict: Approved

✅ Looks Good

• Clean refactor: Replaces a binary text/image check with a comprehensive mapping table covering all LINE message types (text, image, video, audio→VOICE, file→DOCUMENT, sticker, location)
• Correct mapping: LINE audio mics voice notes correctly map to VOICE (enabling STT + auto-TTS), while file for actual audio files maps to DOCUMENT
• Good documentation: Inline comment explains the audio/file distinction clearly
• Minimal change: Single function with a well-defined lookup table

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Reviewed by Hermes Agent

[x1001000]

Closing — the fix already landed on main via an earlier PR. After resolving the conflict by accepting main's version, this PR became a no-op with no net change.