feat(readiness): Effort-based phasing for Portfolio MOD remediation roadmap

## Problem

The Portfolio MOD TD's remediation roadmap currently phases recommendations by **dependency order**, not effort. This leads to unrealistic Phase 1 groupings like "containerize on EKS + migrate 4 databases + build Terraform from scratch" labeled as "Mo 1-2" — which is unrealistic for a team starting from zero, unless you factor in AI-accelerated execution.

Observed in PR #68 test results (Netflix/eureka + pallets/flask portfolio).

## Proposed Fix

### 1. Effort classifier on each recommendation
Add an effort field to each remediation item:
- `trivial` — enable a flag, turn on a service (minutes)
- `config-change` — update config files, add IAM policy (hours)
- `sprint-sized` — containerize an app, set up CI/CD (1-2 weeks)
- `multi-sprint` — migrate databases, rewrite auth layer (weeks-months)

Include both traditional and AI-accelerated estimates.

### 2. Phase gating by effort
- **Phase 0 ("This Week"):** Only `trivial` or `config-change` items
- **Phase 1 ("First Sprint"):** `sprint-sized` items with no blockers
- **Phase 2+ ("Quarter Plan"):** `multi-sprint` items

### 3. Honest phase labels
Replace generic "Mo 1-2" / "Mo 3-4" with:
- "Week 1 Actions" / "This Week Quick Wins"
- "First Sprint"
- "Quarter Plan"

### 4. Quick-win section
Add a dedicated "This Week" section for immediate actions:
- Enable CloudTrail = 15 min
- Tagging standard = 1-2 hrs
- Enable KMS encryption = 30 min
- Turn on GuardDuty = 10 min

### 5. Dual timeline (traditional vs AI-accelerated)
Show two columns:
| Recommendation | Traditional | AI-Accelerated |
|---|---|---|
| Containerize on EKS | 4-6 weeks | 1-2 weeks |
| Migrate DB to Aurora | 6-8 weeks | 2-3 weeks |

The Exec Plan TD already has `ai_acceleration` toggles — mirror that approach here.

## Context

- The **Portfolio Execution Plan TD** (in development) already has `team_size`, `timeline_constraint`, and `ai_acceleration` fields that do effort-to-calendar conversion
- Option A: Add effort-gating to Portfolio MOD TD directly
- Option B: Keep MOD's remediation section lighter and let the Exec Plan TD do the heavy lifting on phasing
- Discuss at Thursday alignment meeting

## Sequencing

- PR #68 (programs update) merges first ✅ — tested and ready
- This improvement = separate follow-up PR against Portfolio MOD TD

## References

- PR #68: https://github.com/aws-samples/aws-transform-custom-samples/pull/68
- Test results showing the phasing issue: PR68-final-test-results portfolio MOD output

Start by reviewing the Portfolio MOD TD implementation and the PR #68 test results that exposed the phasing issue. Compare its remediation structure with the Portfolio Execution Plan TD fields, especially team_size, timeline_constraint, and ai_acceleration. Done means the chosen Option A or B is implemented with effort-based phasing, honest labels, a This Week section, and traditional versus AI-accelerated estimates.

Written by the indexing model from the issue text.