fix: map chat attachments to MCP storage uploads

[eldadfux]

Summary

• Rewrite storage_create_file file args from turn attachment ids/names to MCP inline {filename, content, encoding: base64} before the tool call
• Default file_id to unique() and stop clarifying auto vs custom ID (no way for the user to enter a custom ID)
• Prefer same-turn upload when attachments are present; unit tests cover the write-guard rewrite

Depends on appwrite/mcp#93 (raise MAX_INLINE_BYTES to 10MB).
Cloud clarify attachment carry-forward: https://github.com/appwrite-labs/cloud/pull/3623

Test plan

• Attach an image in Console chat and ask to upload it to a bucket without providing a URL
• Confirm agent does not ask auto vs custom file ID
• Confirm storage_create_file succeeds with inline base64 (not a local path / attachment id string)
• python -m pytest tests/test_write_guard_attachments.py

[greptile-apps]

Greptile Summary

The PR maps chat attachments to MCP inline file payloads before Storage calls and streamlines automatic file ID selection.

• Resolves current-turn attachment IDs or filenames into base64-encoded MCP file objects.
• Applies file resolution within the write-guard argument normalization path.
• Updates agent guidance to use same-turn attachments and default Storage file IDs to unique().

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
app/attachment_upload.py	Adds exact attachment ID/name resolution and converts attachment bytes into the MCP inline base64 file shape.
app/mcp/write_guard.py	Integrates attachment conversion into argument normalization while preserving query normalization.
app/graph/builder.py	Updates workflow guidance for attachment uploads and automatic file ID generation.
app/graph/tools.py	Clarifies the intended roles of attachment inspection and structured ID prompts.

_{Reviews (3): Last reviewed commit: "Remove unused test files for attachment ..." | Re-trigger Greptile}