fix(provider): keep screenshots inline with transport recovery

[sarath-menon]

Restores screenshot delivery to the exact v0.1.21-telemetry.1 provider implementation, removing the screenshot upload adapters and their upload-specific tests. Transport recovery source is byte-for-byte unchanged from v0.1.21-transport-recovery.1.

The previous transport release included all 15 commits between telemetry.1 and screenshot-files.4. Cloud #6394 therefore undid the behavior rollback in #6370.

Red-green proof: the unchanged new regression fails on current main with one upload instead of zero, then passes after restoring inline delivery. Across three real SDK requests it asserts zero uploads/capability calls/deletes, inline image data, no file IDs, and preserved image detail. All seven transport recovery regressions also pass: 8 passed, 0 failed, 59 assertions.

Full provider source comparison to telemetry.1 is empty except the separately retained transport error classification. No documentation, AGENTS, workflow, AWS, or deployment changes in this PR. Staging will require a separate Cloud version/checksum pin and explicit approval.

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Summary by cubic

Restores inline screenshot delivery by removing the screenshot upload adapter (image-files.ts) and its tests, returning to the v0.1.21-telemetry.1 provider behavior while keeping transport recovery unchanged from v0.1.21-transport-recovery.1.

The prior transport release bundled all 15 commits between those two tags, which re-introduced the file-upload path that Cloud #6394 was meant to keep rolled back. Provider tests now assert zero uploads, capability calls, and deletes across real SDK requests, with inline image data and no file IDs, and the transport recovery regressions all still pass.

^{Written for commit 757645b. Summary will update on new commits.}

Live staging acceptance passed

The official serve release 0.1.21-transport-recovery.2 was pinned by Cloud #6414 with its checksum corrected in #6417, then deployed through https://github.com/browser-use/cloud/actions/runs/37720485491 . The actual binary version and SHA256 were verified in live run 072ccdb5-e54d-470a-bbb8-7e519704b647: two screenshots, eight inline image references across seven requests, zero file references, zero Datadog upload events, and independently verified cleanup. tested-in-staging applied. No production deployment.

[cubic-dev-ai]

No issues found across 6 files

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