Add development-scripts agent skill

Ports generic-scripts-module-v1 into a routed skill: module anatomy, shared
loggers/base modules, Taskfile integration, workflows, and pattern decisions.

Fixes a latent defect in the loggers example that silenced all logging in the
module scaffold: loggers/lib/--index-api.sh now sources --env-vars-reader.sh,
and the reader preserves already-exported values so caller overrides still win.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

references/taskfile.md

@@ -0,0 +1,76 @@
+# Taskfile Integration
+
+Exposing module commands through the `task` runner.
+
+Add a module `Taskfile.yml` only when its commands should be discoverable through `task`. A
+module that is only consumed by other modules does not need one.
+
+---
+
+## 1. Module `Taskfile.yml`
+
+```yaml
+# https://taskfile.dev
+
+version: "3"
+
+tasks:
+  initialize-one:
+    cmds:
+      - |
+        ./.scripts/module-example-v1/api/initialize-one.sh {{.CLI_ARGS}}
+    silent: true
+```
+
+Rules:
+
+1. Task names mirror the public `api/` command names, unless an alias is deliberate. A task
+   named differently from the script it runs makes `task --list` output impossible to map back
+   to files.
+2. Forward `{{.CLI_ARGS}}` whenever the command accepts flags.
+3. `silent: true` suppresses task's own command echo, so only the script's logger output
+   appears.
+4. Invoke the `api/` wrapper — never a `lib/` file directly.
+5. The path is repository-root-relative, matching how the scripts source their dependencies.
+
+Arguments pass through after `--`:
+
+```bash
+task module-example-v1:initialize-one -- --name demo --dry-run
+```
+
+Without the `--`, task treats the flags as its own and the script never sees them.
+
+---
+
+## 2. Root `Taskfile.yml` include
+
+```yaml
+includes:
+  module-example-v1: ./.scripts/module-example-v1/Taskfile.yml
+```
+
+Rules:
+
+1. Add a root include only for a module intended as a **stable public task namespace**. The
+   include name becomes a permanent user-facing prefix; renaming it later breaks every
+   documented command and every CI invocation.
+2. Choose a short, clear namespace. Existing examples include `ca`, `kube`, `npmrc`,
+   `repos-local`, and `repos-local-nodejs`.
+3. Do not add includes for experimental or in-progress modules — run them through their `api/`
+   path until the interface settles.
+
+---
+
+## 3. Verifying
+
+```bash
+# Every included namespace and task, with descriptions
+task --list-all
+
+# Confirm a specific task resolves and forwards arguments
+task <module-alias>:<task-name> -- --dry-run
+```
+
+`task --list` shows only tasks carrying a `desc:`; `task --list-all` shows everything. A task
+missing from `--list-all` means the root include is absent or its path is wrong.