fix(ci): remove dead release.yml, add daily schedule, fix project_name casing

Three cleanups from org-wide CI audit:

1. Remove release.yml (dead code): The old workflow_call-triggered release
   workflow has no callers since execute-release.yml now handles releases
   via the PR-merge trigger with reusable-release.yml@main. Leaving both
   creates confusion about which release path is canonical.

2. Add daily schedule to promote-testing-to-main: bluefin and bluefin-lts
   both run at cron '0 23 * * *' in addition to push/dispatch triggers.
   Without the schedule, the promotion PR can go stale if no build pushes
   to testing for a day.

3. Fix project_name: 'Bluefin dakota' -> 'Dakota' to match repo branding
   conventions (bluefin uses 'Bluefin', lts uses 'Bluefin LTS').

Assisted-by: Claude Sonnet 4.6 via GitHub Copilot
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: castrojo

.github/workflows/execute-release.yml

@@ -44,7 +44,7 @@ jobs:
       image: ghcr.io/projectbluefin/dakota
       generate_sbom_inline: true
       checkout_ref: main
-      project_name: Bluefin dakota
+      project_name: Dakota
       badge_label: Stable
       accent_color: "#0ea5e9"
       cert_identity_regexp: >-

.github/workflows/promote-testing-to-main.yml

@@ -12,6 +12,8 @@ on:
   push:
     branches:
       - testing
+  schedule:
+    - cron: '0 23 * * *'
   workflow_dispatch:
 
 concurrency: