chore: replace deprecated labels with issue types in templates (#12355)

# Which Problems Are Solved

The org is migrating from label-based issue classification to GitHub
Issue Types. Issue templates that hardcode `labels:` silently re-add
those labels every time an issue is opened, which blocks the label
cleanup. The `docs` label is also being renamed to `area/docs`, and a
couple of Dependabot labels are being aligned with the new naming
scheme.

# How the Problems Are Solved

Issue templates (these already declare a `type:`, so the deprecated
label is simply removed rather than duplicating the type):

- `.github/ISSUE_TEMPLATE/BUG_REPORT.yaml` — removed `labels: ["bug"]`
(keeps existing `type: Bug`)
- `.github/ISSUE_TEMPLATE/enhancement.yaml` — removed `labels:
["enhancement"]` (keeps existing `type: enhancement`)
- `.github/ISSUE_TEMPLATE/docs.yaml` — `labels: ["docs"]` → `labels:
["area/docs"]`

# Additional Changes

`.github/dependabot.yml` — renamed deprecated label strings in the
`labels:` blocks (the `package-ecosystem` identifiers are left
unchanged):

- `"npm"` → `"javascript"`
- `"gomod"` → `"go"`
- `"documentation"` → `"area/docs"`

# Additional Context

Part of the org-wide migration from label-based issue classification to
GitHub Issue Types.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---
_Generated by [Claude
Code](https://claude.ai/code/session_01MA7kgVw1fjMW32K7FyPASQ)_

Co-authored-by: Livio Spring <[email protected]>

.github/ISSUE_TEMPLATE/BUG_REPORT.yaml

@@ -1,7 +1,6 @@
 name: Bug Report
 description: "Create a bug report to help us improve ZITADEL."
 title: "[Bug]: "
-labels: ["bug"]
 type: Bug
 body:
 - type: markdown

.github/ISSUE_TEMPLATE/docs.yaml

@@ -1,6 +1,6 @@
 name: 📄 Documentation
 description: Create an issue for missing or wrong documentation.
-labels: ["docs"]
+labels: ["area/docs"]
 type: task
 body:
   - type: markdown

.github/ISSUE_TEMPLATE/enhancement.yaml

@@ -1,6 +1,5 @@
 name: 💡 Proposal / Feature request
 description: "Create an issue for a feature request/proposal."
-labels: ["enhancement"]
 type: enhancement
 body:
   - type: markdown

.github/dependabot.yml

@@ -16,7 +16,7 @@ updates:
     interval: weekly
     time: "02:00"
   labels:
-   - "npm"
+   - "javascript"
    - "dependencies"
   open-pull-requests-limit: 10
   commit-message:
@@ -49,7 +49,7 @@ updates:
     interval: weekly
     time: "02:00"
   labels:
-   - "gomod"
+   - "go"
    - "dependencies"
   open-pull-requests-limit: 10
   commit-message:
@@ -101,6 +101,6 @@ updates:
     prefix: chore
     include: scope
   labels:
-    - "npm"
+    - "javascript"
     - "dependencies"
-    - "documentation"
+    - "area/docs"