ci(release): make the Telegram binary notification non-blocking (#174)

The ipctool-release run on master went red even though every build
target compiled and both assets uploaded. The only hard failure was the
"Send binary to Telegram" step: its `curl --max-time 15` to
api.telegram.org timed out (exit 28), and unlike the surrounding
`Build sources` / `Create release` steps it had no `continue-on-error`,
so a flaky notification gated the whole release.

A notification is advisory; it must not fail a release whose build
succeeded and whose assets already uploaded. Add `continue-on-error: true`
to that step (matching the existing treatment of the build and
create-release steps).

Note: the "Create release" step still logs a non-fatal
`already_exists / tag_name` annotation because all matrix targets race to
create the same `latest` tag; it is already `continue-on-error: true`, so
it does not fail the run. Left as-is here.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: widgetii

.github/workflows/release.yml

@@ -155,6 +155,10 @@ jobs:
 
       - name: Send binary to Telegram
         if: steps.build.outcome == 'success'
+        # A notification timing out (curl exit 28 against api.telegram.org)
+        # must never fail a release whose build succeeded and whose assets
+        # already uploaded — keep it advisory.
+        continue-on-error: true
         env:
           TG_TOKEN: ${{ secrets.TELEGRAM_TOKEN_BOT_OPENIPC }}
           TG_CHANNEL: ${{ secrets.TELEGRAM_CHANNEL_OPENIPC_DEV }}