Google Drive connector `create_file` always produces Letter-sized Google Docs, ignoring account default and content-level page-size hints

**Bug description**

Google Docs created via the Google Drive MCP connector's `create_file` tool are always Letter-sized (8.5"×11"), regardless of the user's own Google Docs account default or any page-size hint in the uploaded content.

**Steps to reproduce**

1. Confirm the target Google account's own Docs default is A4 (verified by creating a Doc manually in the Docs UI — it comes out A4).
2. Call `create_file` with `contentMimeType: "text/markdown"` and markdown `textContent`, letting it auto-convert to a Google Doc. Result: Letter.
3. As a workaround attempt, call `create_file` with `contentMimeType: "text/html"` and an explicit page-size hint in the content:
```html
@page { size: 210mm 297mm; margin: 20mm; }
```
Result: still Letter. The content-level hint is ignored.

**Expected behavior**

Either respect the account's own Google Docs default page size, or respect an explicit page-size hint in the uploaded content (HTML `@page` rule or similar), rather than silently forcing Letter regardless of both.

**Context**

This affects any non-US/Canada user of the connector — A4 is the standard page size across most of the world. Notably, Anthropic's own `docx` skill (a different tool, for generating Word files) defaults to A4 with Letter as the explicit opt-in — the opposite default from what this connector does, which suggests this is an oversight rather than an intentional choice.

**Environment:** Google Drive MCP connector (`mcp__Google_Drive__create_file`), via Claude Code.

Start by reproducing through the Google Drive MCP connector's create_file tool, especially mcp__Google_Drive__create_file with text/markdown and text/html plus the @page size rule shown in the issue. Then trace the connector path that converts uploaded content into a Google Doc. Done means created Google Docs no longer silently force Letter when the account default or explicit content hint indicates A4.

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