[TASK][PROGRAMME.T04] Establish the executable feasibility programme

Parent: #1

Task ID: `PROGRAMME.T04`

## Implementation
Run shell/CEF integration, local speech plus inference, all four provider protocols, semantic PC control and resource-profile spikes on declared hardware. Capture alternatives and reject unworkable combinations with evidence.

## Deliverable
P0 feasibility dossier and architecture decisions.

## Verification
Critical embedding, accessibility, cancellation and confinement assumptions are demonstrated by executable spikes before commitments are frozen.

## Guardrail
A failed candidate toolkit or provider surface changes the implementation choice, not the full product vision.

## Prerequisites
- `PROGRAMME.T02`
- `PROGRAMME.T03`

Review: pending · Implementation: not started.

Start with prerequisites PROGRAMME.T02 and PROGRAMME.T03, then run the listed CEF, speech and inference, provider protocol, semantic PC control, and resource-profile spikes on the declared hardware. Record alternatives and evidence for rejected combinations. Done means the P0 feasibility dossier and architecture decisions demonstrate the critical embedding, accessibility, cancellation, and confinement assumptions.

Written by the indexing model from the issue text.