fix(github): use canonical share URL from API instead of constructing it

[xxiaoxiong]

Summary

Fixes GitHub Actions bot comments that were generating broken share links using the old URL format.

Problem

GitHub Actions bot comments append share links like:

https://opencode.ai/s/It7ivB4n

These links now 404. The canonical share URL format has changed to:

https://opncd.ai/share/uaFpXIla

Root Cause

The code was:

1. Calling the share API but ignoring the returned URL
2. Manually constructing the share URL using session.id.slice(-8)
3. Hardcoding the base URL as https://opencode.ai

This broke when:

• The share service started returning different IDs than session IDs
• The base URL changed from opencode.ai to opncd.ai
• The path changed from /s/ to /share/

Solution

Use the canonical share URL returned by the share API instead of constructing it manually.

Before:

await Effect.runPromise(sessionShare.share(session.id))
shareId = session.id.slice(-8)
const link = `${shareBaseUrl}/s/${shareId}`

After:

const result = await Effect.runPromise(sessionShare.share(session.id))
shareUrl = result.url
const link = shareUrl

Changes

packages/opencode/src/cli/cmd/github.ts:

• Renamed shareId to shareUrl to reflect that it now stores the full URL
• Capture result.url from sessionShare.share() instead of deriving from session ID
• Use shareUrl directly in links and comments
• Extract share ID from URL for social card image generation

github/index.ts:

• Same changes for the legacy GitHub action path
• Use SDK client session.share() response: result.data?.share?.url

Testing

• The share API already returns the correct URL format
• Social card image generation still works (extracts ID from URL)
• Comment deduplication still works (checks for full URL in existing comments)
• No runtime behavior changes beyond using the correct URL

Impact

• GitHub Actions comments will now include working share links
• Existing broken links in old comments remain broken (cannot be fixed retroactively)
• Future comments will use the canonical URL format

Fixes #26417

[github-actions]

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Potential duplicate found:

• PR Fix GitHub action share links #26418: "Fix GitHub action share links" - Fix GitHub action share links #26418

This PR appears to be addressing the same issue: fixing broken share links in GitHub Actions bot comments. It's likely either a related fix or a duplicate attempt to resolve the same problem with the canonical share URL format change.

[github-actions]

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