[0.x] Fix PrismTool dropping arguments when provider uses 'input' key

[sumaiazaman]

Fixes #291

Summary

Some AI providers (notably Anthropic) send tool call arguments under the `input` key instead of `arguments`. `PrismTool::toLaravelToolCall()` and `toLaravelToolResult()` only check for `arguments`, silently dropping all arguments when `input` is used.

The Bug

// Tool call from Anthropic uses 'input' key
$toolCall = [
    'id' => 'call_123',
    'name' => 'search',
    'input' => '{"query": "Laravel AI"}',  // 'input' not 'arguments'
];

$result = PrismTool::toLaravelToolCall($toolCall);
$result->arguments; // [] — all arguments silently lost

The Fix

Check `input` as a fallback when `arguments` is not present:

// Before
$toolCall['arguments']['schema_definition'] ?? $toolCall['arguments'] ?? []

// After
$arguments = $toolCall['arguments'] ?? $toolCall['input'] ?? [];

Applied to both `toLaravelToolCall()` and `toLaravelToolResult()`.

Consistency

This follows the same pattern used in PR #326 which fixed the identical issue in `DatabaseConversationStore`.

Changes

• `src/Gateway/Prism/PrismTool.php` — Add `input` key fallback in both methods