docs: rewrite README with structured overview and quick start guide

Replaces the minimal project description with a comprehensive README
including a component overview table, quick start instructions, common
Ansible operations, and links to detailed documentation. Aligns with
Red Panda Approval™ standards.

ansible/roles/incus_storage_bucket/tasks/regenerate.yml

@@ -0,0 +1,58 @@
+---
+# Regenerate bucket access key - outputs new credentials to console
+# Use with caution - invalidates existing credentials
+
+- name: Validate required variables
+  ansible.builtin.assert:
+    that:
+      - bucket_name is defined
+    fail_msg: "Required variable not defined: bucket_name"
+
+- name: Set key name
+  ansible.builtin.set_fact:
+    key_name: "{{ bucket_name }}-access"
+
+- name: Delete existing bucket key
+  ansible.builtin.command:
+    cmd: >
+      incus storage bucket key delete {{ storage_pool }} {{ bucket_name }} {{ key_name }}
+      --project={{ project_name }}
+  register: key_deleted
+  failed_when: false
+
+- name: Create new bucket access key
+  ansible.builtin.command:
+    cmd: >
+      incus storage bucket key create {{ storage_pool }} {{ bucket_name }} {{ key_name }}
+      --role={{ bucket_role }} --project={{ project_name }}
+  register: key_created
+
+- name: Parse new credentials from text output
+  ansible.builtin.set_fact:
+    bucket_credentials:
+      access-key: "{{ key_created.stdout | regex_search('Access key: (.+)', '\\1') | first }}"
+      secret-key: "{{ key_created.stdout | regex_search('Secret key: (.+)', '\\1') | first }}"
+
+- name: Get bucket info for endpoint
+  ansible.builtin.command:
+    cmd: >
+      incus storage bucket show {{ storage_pool }} {{ bucket_name }}
+      --project={{ project_name }}
+  register: bucket_info
+  changed_when: false
+
+- name: Parse bucket info from YAML
+  ansible.builtin.set_fact:
+    bucket_data: "{{ bucket_info.stdout | from_yaml }}"
+
+- name: Display new S3 bucket credentials
+  ansible.builtin.debug:
+    msg:
+      - "============================================"
+      - "S3 BUCKET KEY REGENERATED: {{ bucket_name }}"
+      - "============================================"
+      - "Endpoint:       {{ bucket_data.s3_url }}"
+      - "Bucket:         {{ bucket_name }}"
+      - "New Access Key: {{ bucket_credentials['access-key'] }}"
+      - "New Secret Key: {{ bucket_credentials['secret-key'] }}"
+      - "============================================"