fix(ci): remove kubernetes-deploy workflow that leaked secrets to logs

The workflow ran on every push to every branch and deployed nothing.
It echoed the raw Vault login response, the Kanidm API token response
and the OIDC token response to the job log, dumped the environment,
and configured kubectl with --insecure-skip-tls-verify.

Deployment is handled by gitops-update.yaml. Docs updated to describe
that flow; T1 marked done in the cleanup task list.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitea/workflows/kubernetes-deploy.yaml

@@ -1,111 +0,0 @@
-name: Deploy to K8s
-on:
-  workflow_dispatch:
-  push:
-    branches:
-      - '**'
-jobs:
-  deploy:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Debug - print Gitea Actions environment
-        run: |
-          echo "=== All environment variables ==="
-          env | sort
-          echo ""
-          echo "=== GITHUB_* / GITEA_* / ACTIONS_* vars ==="
-          env | grep -E '^(GITHUB|GITEA|ACTIONS)_' | sort
-
-      - name: Install kubectl
-        run: |
-          curl -sfLO "https://dl.k8s.io/release/$(curl -sfL https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
-          install kubectl /usr/local/bin/
-
-      - name: Get Kanidm token from Vault
-        id: vault
-        run: |
-          set -euxo pipefail
-
-          VAULT_AUTH_RESPONSE=$(curl -f --request POST \
-            --data '{"role_id":"${{ secrets.VAULT_ROLE_ID }}","secret_id":"${{ secrets.VAULT_SECRET_ID }}"}' \
-            https://vault.hrajfrisbee.cz/v1/auth/approle/login)
-
-          echo "Vault auth response: $VAULT_AUTH_RESPONSE" >&2
-          VAULT_TOKEN=$(echo "$VAULT_AUTH_RESPONSE" | jq -r '.auth.client_token')
-
-          # Read the kanidm API token
-          SECRET_RESPONSE=$(curl -f \
-            -H "X-Vault-Token: ${VAULT_TOKEN}" \
-            https://vault.hrajfrisbee.cz/v1/secret/data/gitea/gitea-ci)
-
-          echo "Secret response: $SECRET_RESPONSE" >&2
-          API_TOKEN=$(echo "$SECRET_RESPONSE" | jq -r '.data.data.token')
-
-          echo "::add-mask::${API_TOKEN}"
-          echo "api_token=${API_TOKEN}" >> "$GITHUB_OUTPUT"
-
-      - name: Exchange for K8s OIDC token via Kanidm
-        id: k8s
-        run: |
-          API_TOKEN="${{ steps.vault.outputs.api_token }}"
-          echo "api_token length: ${#API_TOKEN}" >&2
-          echo "api_token prefix (first 8 chars): ${API_TOKEN:0:8}..." >&2
-
-          HTTP_BODY=$(mktemp)
-          HTTP_STATUS=$(curl -sS -X POST "https://idm.home.hrajfrisbee.cz/oauth2/token" \
-            -d "grant_type=urn:ietf:params:oauth:grant-type:token-exchange" \
-            -d "client_id=k8s" \
-            -d "subject_token=${API_TOKEN}" \
-            -d "subject_token_type=urn:ietf:params:oauth:token-type:access_token" \
-            -d "audience=k8s" \
-            -d "scope=openid groups" \
-            -o "$HTTP_BODY" -w "%{http_code}")
-
-          echo "HTTP status: $HTTP_STATUS" >&2
-          echo "Response body:" >&2
-          cat "$HTTP_BODY" >&2
-
-          RESPONSE=$(cat "$HTTP_BODY")
-          ID_TOKEN=$(echo "$RESPONSE" | jq -r '.id_token // empty')
-
-          if [ -z "$ID_TOKEN" ]; then
-            echo "::error::Kanidm token exchange failed (HTTP $HTTP_STATUS)"
-            exit 1
-          fi
-
-          echo "::add-mask::${ID_TOKEN}"
-          echo "id_token=${ID_TOKEN}" >> "$GITHUB_OUTPUT"
-
-          # Sanity check
-          # Warning - this is the part that is failing
-          # echo "$ID_TOKEN" | cut -d. -f2 | base64 -d 2>/dev/null | jq '{sub, groups, exp}'
-
-
-      - name: Debug - print environment before kubectl
-        run: env | sort
-
-      - name: Configure kubectl & deploy
-        run: |
-          echo "${{ secrets.K8S_CA_CERT }}" > /tmp/ca.crt
-          
-          kubectl config set-cluster mycluster \
-            --server=https://192.168.0.31:6443 \
-            --insecure-skip-tls-verify=true          
-          # --certificate-authority=/tmp/ca.crt \
-
-          kubectl config set-credentials gitea-ci \
-            --token="${{ steps.k8s.outputs.id_token }}"
-
-          kubectl config set-context gitea-ci \
-            --cluster=mycluster --user=gitea-ci
-
-          kubectl config use-context gitea-ci
-
-          kubectl auth whoami
-          kubectl get ns
-
-          # your deploy here
-          # kubectl apply -f k8s/