Update tooling dependencies (Feb 2026 cycle) (#254)

## Summary

Monthly tooling dependency update cycle:

- **Pre-commit hooks**: trufflehog v3.92.5→v3.93.4, ruff v0.14.13→v0.15.2, shellcheck v0.10.0.1→v0.11.0.1, prettier v3.8.0→v3.8.1, actionlint v1.7.10→v1.7.11
- **Fly.io Dockerfile**: pin nginx to 1.28.2-alpine (was unpinned), bump alloy v1.5.1→v1.13.1
- **Mise tasks**: normalize httpx lower bound to >=0.28.0 and typer to >=0.15.0 across all scripts
- **Forgejo workflows**: actions/checkout@v4 is current, no changes needed
- **New how-to doc**: [[update-tooling-dependencies]] documenting this monthly cycle

## No changes needed

- pre-commit-hooks v6.0.0, yamllint v1.38.0, shfmt v3.12.0-2, taplo v0.9.3, ansible-lint 26.1.1 — all already at latest

## Test plan

- [x] `uvx pre-commit run --all-files` — all 24 hooks pass
- [ ] Fly.io deploy (triggered automatically on merge to main via deploy-fly workflow)

Reviewed-on: https://forge.ops.eblu.me/eblume/blumeops/pulls/254

.pre-commit-config.yaml

@@ -20,7 +20,7 @@ repos:
 
   # Secret detection
   - repo: https://github.com/trufflesecurity/trufflehog
-    rev: v3.92.5
+    rev: v3.93.4
     hooks:
       - id: trufflehog
         entry: trufflehog git file://. --since-commit HEAD --no-verification --fail
@@ -47,7 +47,7 @@ repos:
 
   # Python - ruff for linting and formatting
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.14.13
+    rev: v0.15.2
     hooks:
       - id: ruff
         args: ['--fix']
@@ -55,7 +55,7 @@ repos:
 
   # Shell scripts - shellcheck and shfmt
   - repo: https://github.com/shellcheck-py/shellcheck-py
-    rev: v0.10.0.1
+    rev: v0.11.0.1
     hooks:
       - id: shellcheck
         args: ['--severity=warning']
@@ -75,7 +75,7 @@ repos:
 
   # JSON formatting (prettier for consistent style)
   - repo: https://github.com/rbubley/mirrors-prettier
-    rev: v3.8.0
+    rev: v3.8.1
     hooks:
       - id: prettier
         types_or: [json]
@@ -83,7 +83,7 @@ repos:
 
   # GitHub/Forgejo Actions workflow linting
   - repo: https://github.com/rhysd/actionlint
-    rev: v1.7.10
+    rev: v1.7.11
     hooks:
       - id: actionlint-system
         args: ['-config-file', '.github/actionlint.yaml']