fix(backup): Add the site name to streamed backup file names

[regdocs]

Streamed backups were named <timestamp>-%stream%-<type> locally and <timestamp>-stream-<type> in S3, so, unlike regular backups, nothing in the object or downloaded file name said which site it belongs to.

This adds frappe's site slug (the site name with dots turned into underscores, as regular backups use), keeping the stream label:

• Local FIFO: 20260929_101500-my_site_test-%stream%-database.sql.gz
• S3 object: 20260929_101500-my_site_test-stream-database.sql.gz

The slug goes before the %stream% marker on purpose. Frappe finds recent backups with the glob *-<slug>-database.sql.gz, and a name ending in -<slug>-database.sql.gz would match a live FIFO, which blocks when opened.

Still working:

• bypass_unlink.so matches %stream% anywhere in the path (strstr), so the FIFOs keep their protection.
• The %stream%- → stream- swap for S3 keys and the pkill -f <timestamp> cleanup don't change.
• Nothing in press parses these names.

🤖 Generated with Claude Code

[mergify]

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[greptile-apps]

Confidence Score: 4/5

[Medium risk] Changes how backup file names are constructed during streaming.

The filename flow appears sound, but the repository’s public-function documentation requirement must be met before merging.

_{Reviews (1) · Last reviewed commit: "fix(backup): Add the site name to stream..."}

[greptile-apps]

Public method lacks docstring The new streamed_backup_prefix method has no docstring. The repository’s Frappe review guideline requires public functions to be documented; add one before merging.

Context Used: Guidelines for reviewing Frappe Framework applications. (source)

Prompt To Fix With AI

This is a comment left during a code review.
Path: agent/site.py
Line: 1005

Comment:
**Public method lacks docstring** The new `streamed_backup_prefix` method has no docstring. The repository’s Frappe review guideline requires public functions to be documented; add one before merging.

**Context Used:** Guidelines for reviewing Frappe Framework applications. ([source](https://github.com/frappe/skills/blob/main/skills/quality-code-review/SKILL.md))

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For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

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[greptile-apps]

S3 filename remains untested This test checks the FIFO name but not the resulting S3 object name. Assert that the %stream%- marker becomes stream- in the object name so a regression in that conversion cannot pass unnoticed.

Prompt To Fix With AI

This is a comment left during a code review.
Path: agent/tests/test_site.py
Line: 385-388

Comment:
**S3 filename remains untested** This test checks the FIFO name but not the resulting S3 object name. Assert that the `%stream%-` marker becomes `stream-` in the object name so a regression in that conversion cannot pass unnoticed.

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For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.