[TASK][PROGRAMME.T05] Build the cross-workstream dependency and ownership graph

Parent: #1

Task ID: `PROGRAMME.T05`

## Implementation
Classify each dependency as contract prerequisite, implementation prerequisite, integration gate or external access condition. Assign task owners and identify parallel start opportunities without treating maturity phases as blanket blockers.

## Deliverable
Reviewable dependency graph and staffing allocation.

## Verification
The graph has no unexplained cycle and partnership/hardware research can begin before full SDK/runtime maturity.

## Guardrail
Do not solve scheduling conflicts by weakening authorization or pretending fixture-only capabilities are live.

## Prerequisites
- `PROGRAMME.T03`
- `PROGRAMME.T04`

Review: pending · Implementation: not started.

Start by reviewing the prerequisite tasks PROGRAMME.T03 and PROGRAMME.T04, then map the dependency types, owners, and parallel-start opportunities described here. Done means a reviewable graph and staffing allocation with no unexplained cycle, while partnership and hardware research can start before full SDK/runtime maturity.

Written by the indexing model from the issue text.