Migrate GitHub Actions to Blacksmith runners (#278)

- Replace GitHub-hosted ubuntu runners with Blacksmith equivalents
- Remove unused/deprecated workflow files where applicable
- Use blacksmith-4vcpu-ubuntu-2404 for builds and tests
- Use blacksmith-2vcpu-ubuntu-2404 for lightweight jobs

Author: jai-deepsource

.github/workflows/CI.yml

@@ -8,7 +8,7 @@ on:
 
 jobs:
   run-tests:
-    runs-on: ubuntu-latest
+    runs-on: blacksmith-4vcpu-ubuntu-2404
     permissions:
       id-token: write # Required to fetch the OIDC token
 

.github/workflows/build-and-deploy.yml

@@ -14,7 +14,7 @@ env:
 
 jobs:
   resolve-env:
-    runs-on: ubuntu-latest
+    runs-on: blacksmith-4vcpu-ubuntu-2404
     outputs:
       environment: ${{ steps.resolve.outputs.environment }}
       base_url: ${{ steps.resolve.outputs.base_url }}
@@ -38,7 +38,7 @@ jobs:
 
   build-linux:
     needs: resolve-env
-    runs-on: ubuntu-latest
+    runs-on: blacksmith-4vcpu-ubuntu-2404
     strategy:
       matrix:
         include:
@@ -176,7 +176,7 @@ jobs:
 
   build-windows:
     needs: resolve-env
-    runs-on: ubuntu-latest
+    runs-on: blacksmith-4vcpu-ubuntu-2404
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
@@ -215,7 +215,7 @@ jobs:
 
   deploy:
     needs: [resolve-env, build-linux, build-darwin, build-windows]
-    runs-on: ubuntu-latest
+    runs-on: blacksmith-4vcpu-ubuntu-2404
     steps:
       - uses: actions/checkout@v4