Fix publish summary rendering "❓ no result" for every package

[Copilot]

The v0.7.1 release notes showed "❓ no result" across the entire publish summary table, even though every package (including the new go/python ext packs) published successfully.

Root cause

Publishing a brand-new pack for the first time triggers a 404 from gh api, which prints its raw, unfiltered error body to stdout even with --jq and 2>/dev/null. That JSON body's embedded quotes leaked through a step output and got interpolated directly via ${{ }} into a jq --arg invocation, breaking its quoting and corrupting the whole call into emitting a bare true/false instead of a JSON object. The summary script then indexed that stray boolean while iterating all fragments, aborting the render for every cell instead of just the broken ones.

Changes

• check_version steps (all 4 publish jobs): force PUBLISHED_VERSION empty on any gh api failure instead of relying on 2>/dev/null || true, which doesn't stop a leaked stdout error body.
• Record publish result steps (all 4 publish jobs): pass previous_version/target_version through env: and reference them as shell variables instead of interpolating ${{ }} directly into the jq --arg line, so embedded quotes can no longer corrupt the invocation.
• build-publish-summary.sh: filter out non-object fragments in cell() so one malformed result only affects its own cell instead of the entire table.

# before: leaks gh api's raw error body into PUBLISHED_VERSION
PUBLISHED_VERSION=$(gh api .../versions --jq '...' 2>/dev/null || true)

# after: forces empty on any failure
if ! PUBLISHED_VERSION=$(gh api .../versions --jq '...' 2>/dev/null); then
  PUBLISHED_VERSION=""
fi

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Review details

• Files reviewed: 8/8 changed files
• Comments generated: 6
• Review effort level: Low

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