[codex] Improve mobile org chart navigation (#4127)

## Thinking Path

> - Paperclip models companies as teams of human and AI operators
> - The org chart is the primary visual map of that company structure
> - Mobile users need to pan and inspect the chart without awkward
gestures or layout jumps
> - The roadmap also needed to reflect that the multiple-human-users
work is complete
> - This pull request improves mobile org chart gestures and updates the
roadmap references
> - The benefit is a smoother company navigation experience and docs
that match shipped multi-user support

## What Changed

- Added one-finger mobile pan handling for the org chart.
- Expanded org chart test coverage for touch gesture behavior.
- Updated README, ROADMAP, and CLI README references to mark
multiple-human-users work as complete.

## Verification

- `pnpm install --frozen-lockfile --ignore-scripts`
- `pnpm exec vitest run ui/src/pages/OrgChart.test.tsx`
- Result: 4 tests passed.

## Risks

- Low-medium risk: org chart pointer/touch handling changed, but the
behavior is scoped to the org chart page and covered by targeted tests.

> For core feature work, check [`ROADMAP.md`](ROADMAP.md) first and
discuss it in `#dev` before opening the PR. Feature PRs that overlap
with planned core work may need to be redirected — check the roadmap
first. See `CONTRIBUTING.md`.

## Model Used

- OpenAI Codex coding agent based on GPT-5, tool-enabled local shell and
GitHub workflow, exact runtime context window not exposed in this
session.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] If this change affects the UI, I have included before/after
screenshots, or documented why targeted interaction tests are sufficient
here
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Paperclip <noreply@paperclip.ing>

ROADMAP.md

@@ -44,7 +44,7 @@ Budgets are a core control-plane feature, not an afterthought. Better budgeting
 
 Paperclip should support explicit review and approval stages as first-class workflow steps, not just ad hoc comments. That means reviewer routing, approval gates, change requests, and durable audit trails that fit the same task model as the rest of the control plane.
 
-### ⚪ Multiple Human Users
+### ✅ Multiple Human Users
 
 Paperclip needs a clearer path from solo operator to real human teams. That means shared board access, safer collaboration, and a better model for several humans supervising the same autonomous company.