[fix] Truncate large query profiles after MergedProfile

[Ragnaroos]

Summary

• accept local Query Profile files up to 100 MiB
• reduce files over 10 MiB before upload by retaining Summary and MergedProfile
• remove per-instance DetailProfile/Execution Profile sections
• keep the final upload within the existing 10 MiB backend limit
• prevent stale asynchronous file preparation from replacing a newer selection
• add focused tests for truncation boundaries, UTF-8 byte size, and file limits

Why

Large Apache Doris Query Profiles can exceed the backend's 10 MiB upload limit because they contain extensive per-instance DetailProfile data.

Summary and MergedProfile retain the aggregated execution metrics needed for the initial diagnosis. Removing the following per-instance sections allows large Profiles to use the existing analysis API without increasing the backend request limit.

Truncation is only performed when a MergedProfile header is followed by a recognized per-instance profile header. Files that cannot be reduced safely to 10 MiB are rejected.

Validation

• node --test src/components/profile-analysis/*.test.js
  • 51 tests passed
• targeted TypeScript compilation passed
• verified with a 41,070,035-byte real Profile
  • output: 123,362 bytes
  • MergedProfile retained
  • DetailProfile removed