fix(acp): accept https:// URIs in image content blocks

[truenorth-lj]

Issue for this PR

Closes #24815

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

packages/opencode/src/acp/agent.ts:1394 previously read:

} else if (part.uri && part.uri.startsWith("http:")) {

That prefix only matches http:// — https:// fails the check (the 5th char is s, not :), so the entire case "image": branch falls through and parts.push never runs. The image is silently dropped from the prompt with no error.

This breaks ACP clients doing two-stage uploads (sign a GCS / S3 URL, pass the https:// URL via the ACP image block instead of inlining base64).

This PR aligns the check with the rest of the codebase, where every other URL test uses both prefixes:

File	Pattern
packages/opencode/src/session/instruction.ts:146,168	startsWith("https://") || startsWith("http://")
packages/opencode/src/cli/cmd/import.ts:98	startsWith("http://") || startsWith("https://")
packages/opencode/src/tool/webfetch.ts:23	!startsWith("http://") && !startsWith("https://")
packages/opencode/src/config/config.ts:1270	startsWith("http://") || startsWith("https://")

The fix is one line:

-          } else if (part.uri && part.uri.startsWith("http:")) {
+          } else if (part.uri && (part.uri.startsWith("http://") || part.uri.startsWith("https://"))) {

This matches what the surrounding code clearly intends — parseUri(part.uri) two lines above already accepts both schemes — and brings this branch in line with the conventions used everywhere else in the repo.

How did you verify your code works?

Reproduced the bug locally before the fix:

1. Run a local ACP client that sends session/prompt with { "type": "image", "uri": "https://example.com/x.png", "mimeType": "image/png" }.
2. Inspect the parts array passed downstream — image part is missing.
3. Apply the patch.
4. Repeat — image part is now present with url set to the https:// URL.

The change is the most narrowly scoped possible (one boolean expression), and there are no tests for the surrounding case "image": switch in this file, so I haven't added one in this PR — happy to add one if you point me at the test file pattern you'd want.

Screenshots / recordings

N/A (no UI change).

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[truenorth-lj]

Polite nudge — this has been open for 4 days with CI green and no conflicts on dev.

The fix is a one-line typo (startsWith("http:") → startsWith("http://") || startsWith("https://")). Every other URL check in the codebase pairs both prefixes; only this one is missing https://, silently dropping images for any ACP client doing two-stage signed-URL uploads (GCS / S3 / Cloudfront).

@kitlangton — would you have a moment to look? Happy to add a unit test or split if anything's off.

I also just opened a related ACP fix (#25422 / issue #25421) — different bug, same area. Same offer there: regression test on request.

[truenorth-lj]

@rekram1-node — would you have a moment to look at this one? It's been open 10 days with CI green and no conflicts.

The fix is one line (startsWith("http:") → startsWith("http://") || startsWith("https://")) — every other URL check in the codebase already pairs both prefixes, only this one was missing https://, which silently drops images for any ACP client doing two-stage signed-URL uploads (GCS / S3 / Cloudfront).

Saw you've been merging ACP-area PRs from external contributors recently (#25698, #25591) — hoping to reach the right reviewer. Happy to add a regression test against createFakeAgent if useful, or feel free to push back if anything's off.

Also — if there's a path to getting onto the contributor / vouch list so future ACP fixes don't sit in the unfiltered queue, I'd appreciate the pointer.

[truenorth-lj]

Hey — just doing housekeeping on stale PRs. Happy to close this one if the approach isn't right, or if it's blocked on anything I haven't addressed.

The fix is a one-line startsWith("http:") → startsWith("http://") || startsWith("https://") to match every other URL check in the codebase, but no worries if it doesn't fit upstream priorities right now — just let me know either way and I'll act on it.