Implement fallback frame matching by function name and module (Fixes VROOM-5B)

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Description

This PR implements fallback frame matching by function name and module to fix the issue where a regressed function's fingerprint doesn't match any frame in the profile data.

Problem

When the client sends a regressed function payload with a fingerprint, GetFrameWithFingerprint fails to find a matching frame because:

1. The fingerprint computed by the client SDK differs from vroom's computation
2. Differences in module/package extraction (e.g., trimPackage behavior)
3. Edge cases in fingerprint computation (format, encoding, normalization)

This results in the error "Unable to find matching frame" and the regressed function is skipped.

Solution

Implemented a multi-tiered fallback approach:

1. First attempt: Exact fingerprint match (existing behavior)
2. Fallback: Try alternative fingerprint calculations for each frame:
   • Raw package path instead of trimmed package
   • File path instead of module/package
   • Module alone (ignoring package)
   • Function name alone (empty module)

Key Changes

• Added FindFrameByFingerprintWithFallback() helper function in the frame package
• Updated GetFrameWithFingerprint() in:
  • SampleChunk (chunk/sample.go)
  • AndroidChunk (chunk/android.go)
  • sample.Profile (sample/sample.go)
  • profile.Android (profile/android.go)
• Added structured logging when fallback matching is used, including:
  • Target fingerprint
  • Matched frame fingerprint
  • Function name and module
  • Profile/Chunk IDs for debugging
• Added comprehensive tests for fallback functionality
• Graceful degradation: if both exact and fallback fail, returns ErrFrameNotFound

Testing

• All existing tests pass
• Added new tests in frame_fallback_test.go covering:
  • Exact matches
  • Fallback matches with different fingerprint variations
  • No match scenarios
  • Fingerprint variation computation

Impact

• Increases resilience when fingerprint computation differs between client and server
• Provides debugging visibility through structured logging
• No breaking changes - existing exact match behavior is preserved
• Graceful fallback only when needed

Fixes VROOM-5B