revert: remove EventListener (Tekton Triggers not installed)

Keep it simple: use gitea workflow to trigger Tekton pipeline
Tekton is sole executor, gitea is sole trigger point
Avoids needing to install Tekton Triggers component

k8s/tekton/eventlistener.yaml

@@ -1,143 +0,0 @@
----
-# Tekton EventListener: Git webhook → PipelineRun
-# Listens on HTTP for Forgejo push events, triggers pipeline
-
-apiVersion: triggers.tekton.dev/v1beta1
-kind: EventListener
-metadata:
-  name: poimen-memory-listener
-  namespace: poimen
-spec:
-  serviceAccountName: tekton-triggers
-  triggers:
-  - name: on-push
-    interceptors:
-    - ref:
-        name: "github"
-      params:
-      - name: "secretRef"
-        value:
-          secretName: github-secret
-          secretKey: secretToken
-      - name: "eventTypes"
-        value:
-        - "push"
-    - name: "filter"
-      ref:
-        name: "cel"
-      params:
-      - name: "filter"
-        value: |
-          body.ref in ['refs/heads/main', 'refs/heads/feat/production-ingest-test-logging'] &&
-          (body.commits[0].modified.exists(x, x.startsWith('migrations/')) ||
-           body.commits[0].modified.exists(x, x.startsWith('crates/')) ||
-           body.commits[0].modified.exists(x, x.startsWith('k8s/tekton/')))
-    template:
-      ref: poimen-pipelinerun-template
-    bindings:
-    - ref: poimen-pipelinebinding
-
----
-# TriggerTemplate: defines what PipelineRun to create
-apiVersion: triggers.tekton.dev/v1beta1
-kind: TriggerTemplate
-metadata:
-  name: poimen-pipelinerun-template
-  namespace: poimen
-spec:
-  params:
-  - name: gitrevision
-    description: git revision
-  - name: gitrepositoryurl
-    description: git repo URL
-  - name: gitrepositoryname
-    description: git repo name
-  resourcetemplates:
-  - apiVersion: tekton.dev/v1
-    kind: PipelineRun
-    metadata:
-      generateName: poimen-ci-
-      namespace: poimen
-    spec:
-      pipelineRef:
-        name: poimen-ci
-      params:
-      - name: image
-        value: "forgejo.riotpiao.com/riotpiao-poimen/poimen-memory:$(tt.params.gitrevision)"
-      - name: git-revision
-        value: "$(tt.params.gitrevision)"
-      - name: git-repo-url
-        value: "$(tt.params.gitrepositoryurl)"
-      workspaces:
-      - name: source
-        persistentVolumeClaim:
-          claimName: tekton-source-pvc
-      serviceAccountName: tekton-builder
-      timeout: 2h
-
----
-# TriggerBinding: extracts fields from git webhook
-apiVersion: triggers.tekton.dev/v1beta1
-kind: TriggerBinding
-metadata:
-  name: poimen-pipelinebinding
-  namespace: poimen
-spec:
-  params:
-  - name: gitrevision
-    value: $(body.after)
-  - name: gitrepositoryurl
-    value: $(body.repository.clone_url)
-  - name: gitrepositoryname
-    value: $(body.repository.name)
-
----
-# ServiceAccount for Tekton Triggers
-apiVersion: v1
-kind: ServiceAccount
-metadata:
-  name: tekton-triggers
-  namespace: poimen
-
----
-# Role for Tekton Triggers (create PipelineRuns)
-apiVersion: rbac.authorization.k8s.io/v1
-kind: Role
-metadata:
-  name: tekton-triggers-role
-  namespace: poimen
-rules:
-- apiGroups: ["tekton.dev"]
-  resources: ["pipelineruns"]
-  verbs: ["create", "get", "list", "watch"]
-- apiGroups: ["tekton.dev"]
-  resources: ["taskruns"]
-  verbs: ["create", "get", "list", "watch"]
-
----
-# RoleBinding
-apiVersion: rbac.authorization.k8s.io/v1
-kind: RoleBinding
-metadata:
-  name: tekton-triggers-rolebinding
-  namespace: poimen
-roleRef:
-  apiGroup: rbac.authorization.k8s.io
-  kind: Role
-  name: tekton-triggers-role
-subjects:
-- kind: ServiceAccount
-  name: tekton-triggers
-  namespace: poimen
-
----
-# Secret for webhook token (base64 encoded)
-# kubectl create secret generic github-secret --from-literal=secretToken=your-webhook-secret -n poimen
-apiVersion: v1
-kind: Secret
-metadata:
-  name: github-secret
-  namespace: poimen
-type: Opaque
-stringData:
-  secretToken: "changeme-use-sops-encryption"