refactor: update Dockerfile and authentication flow for improved user experience

- Updated Dockerfile to create a cache directory for Next.js runtime, ensuring proper permissions and ownership.
- Enhanced the authentication flow by updating the magic link expiration time from 5 to 15 minutes, improving user experience and reducing login issues.
- Added user-friendly error handling for invalid or expired magic links, providing clear feedback on the login page.
- Adjusted email templates to reflect the new 15-minute validity period for magic links.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

.claude/settings.json

@@ -1,7 +1,7 @@
 {
   "enabledPlugins": {
-    "superpowers@superpowers-marketplace": true,
-    "prd-development@pm-skills": true
+    "superpowers@superpowers-marketplace": false,
+    "prd-development@pm-skills": false
   },
   "extraKnownMarketplaces": {
     "superpowers-marketplace": {

.claude/skills/grill-me/SKILL.md

@@ -1,7 +0,0 @@
----
-name: grill-me
-description: A relentless interview to sharpen a plan or design.
-disable-model-invocation: true
----
-
-Run a `/grilling` session.

.claude/skills/grilling/SKILL.md

@@ -1,22 +0,0 @@
----
-name: grilling
-description: Grill the user relentlessly about a plan, decision, or idea. Use when the user wants to stress-test their thinking, or uses any 'grill' trigger phrases.
----
-
-Interview the user relentlessly until you reach a shared understanding. Map this as a **design tree**: every decision branches into the decisions that hang off it.
-
-Work the tree in **rounds**. The **frontier** is every decision whose prerequisites are already settled — the questions you can ask _now_ without guessing at answers you haven't heard yet. Ask the whole frontier in one round: number each question and give your recommended answer. Then wait for the user's answers before the next round.
-
-Each question should be formatted like so:
-
-```
-❓ **Q1** - **<question title>**: <question body, might be multiple paragraphs, including multiple choices>
-
-➡️ <your recommended answer>
-```
-
-Each round the user answers reshapes the tree — settled decisions push the frontier outward and unblock questions that depended on them. Recompute the frontier and ask the next round. A question whose answer depends on another question still open in this round belongs to a _later_ round, not this one.
-
-Finding _facts_ is your job, never the user's. When a frontier question needs a fact from the environment (filesystem, tools, etc.), dispatch a sub-agent to find it — don't ask the user for anything you could look up yourself. Don't block on it: a running exploration is an unsettled prerequisite, so only the questions downstream of it wait for the sub-agent to report — ask the rest of the frontier now. The _decisions_ are the user's — put each to them and wait.
-
-The session is done when the frontier is empty: every branch of the design tree visited, nothing left silently assumed. Do not act on it until the user confirms you have reached a shared understanding.