feat(ev): add is_suspended/suspended_since to EVOpportunity (#14)

## What

Adds two additive, optional fields to the `EVOpportunity` pydantic
model:

- `is_suspended: bool = False` — true while a live opp's sharp reference
is momentarily suspended
- `suspended_since: float | None = None` — unix seconds the suspension
began (present only when suspended)

## Why

Mirrors the server-side flag-gated suspended-opportunity state shipped
in **sharp-api-go #789** (`EV_SUSPENDED_STATE`). When Pinnacle (the
sharp ref) suspends a live market, the engine now keeps the opp
**visible-but-suspended** with the same stable `id` and the **edge
hidden** (`ev_percentage` 0 / unknown — never a stale edge), instead of
dropping it and re-adding on resume — eliminating live EV flicker. SDK
consumers need the field to render the suspended state and to keep the
row in place across resume.

## Safety / compatibility

- Purely **additive optional** fields with safe defaults (`False` /
`None`) — mirrors the `team_side`/`market_segment` precedent.
- **Inert until the server flag flips:** absent from the wire unless
`EV_SUSPENDED_STATE=1` on the API. Today (flag off) the wire is
byte-identical, so fully backward-compatible. No version bump.
- `py_compile` + a pydantic round-trip (suspended payload **and**
flag-off default shape) pass.

Type: feat

Co-authored-by: paperclip-resolver[bot] <paperclip-resolver[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: 3 people

src/sharpapi/models.py

@@ -302,6 +302,12 @@ class EVOpportunity(BaseModel):
     # Structured side/segment axes (issue #76 / #689), additive + optional.
     team_side: str | None = None
     market_segment: str | None = None
+    # Suspended-state (server flag EV_SUSPENDED_STATE), additive + optional. While the sharp
+    # reference is momentarily suspended the opp stays visible with is_suspended=True and the
+    # edge hidden (ev_percentage is 0 / unknown — never a stale edge); suspended_since is the
+    # unix-seconds timestamp the suspension began. Absent unless the server flag is enabled.
+    is_suspended: bool = False
+    suspended_since: float | None = None
     # Optional structured refs (additive, non-breaking).
     home: TeamRef | None = None
     away: TeamRef | None = None