feat(errors): add OFFSET_TOO_LARGE code (#3)

* feat(errors): add OFFSET_TOO_LARGE code

an upstream change introduces a new HTTP 400 error code
`offset_too_large` returned by /api/v1/odds and /api/v1/odds/delta
when clients request offset > 500. Adding the canonical code here
so consumers branching on errcode strings can recognize it.

Mapped to ValidationError — clients treating the request as retriable
with a corrected offset can handle it the same way they handle
validation errors. Description points to cursor-based pagination and
since-advancement as the structured alternatives.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* style: wrap OFFSET_TOO_LARGE description to satisfy ruff E501

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Mlaz-code

src/sharpapi/exceptions.py

@@ -83,6 +83,7 @@ class StreamError(SharpAPIError):
 MISSING_API_KEY = "missing_api_key"
 NOT_FOUND = "not_found"
 NOT_READY = "not_ready"
+OFFSET_TOO_LARGE = "offset_too_large"
 RATE_LIMITED = "rate_limited"
 SERVICE_UNAVAILABLE = "service_unavailable"
 TIER_RESTRICTED = "tier_restricted"
@@ -115,6 +116,10 @@ class StreamError(SharpAPIError):
     MISSING_API_KEY: "No API key provided.",
     NOT_FOUND: "Resource not found.",
     NOT_READY: "A required backing store is not yet ready to serve this request; retry shortly.",
+    OFFSET_TOO_LARGE: (
+        "offset exceeds the per-endpoint maximum; "
+        "use cursor-based pagination or advance `since`."
+    ),
     RATE_LIMITED: "Rate limit exceeded; see Retry-After header.",
     SERVICE_UNAVAILABLE: "Service is temporarily unavailable.",
     TIER_RESTRICTED: "Current subscription tier does not include this feature.",
@@ -150,6 +155,7 @@ class StreamError(SharpAPIError):
     TOO_MANY_STREAMS: RateLimitedError,
     # Validation
     VALIDATION_ERROR: ValidationError,
+    OFFSET_TOO_LARGE: ValidationError,
     # Streaming frames
     WS_ALREADY_AUTHENTICATED: StreamError,
     WS_INVALID_MESSAGE: StreamError,