docs: consolidate documentation into organized structure

- Move 12 markdown files from root to docs/ subdirectories
- Organize documentation by category:
  • docs/troubleshooting/ (1 file)  - Technical troubleshooting guides
  • docs/deployment/      (4 files) - Deployment and security documentation
  • docs/guides/          (3 files) - Feature-specific guides
  • docs/planning/        (4 files) - Planning and improvement proposals

Root directory cleanup:
- Reduced from 16 to 4 markdown files in root
- Only essential project files remain:
  • CLAUDE.md (AI instructions)
  • README.md (Main project readme)
  • CLEANUP_PLAN.md (Current cleanup plan)
  • SRC_STRUCTURE_IMPROVEMENTS.md (Structure improvements)

This improves:
✅ Documentation discoverability
✅ Logical organization by purpose
✅ Clean root directory
✅ Better maintainability

src/Framework/OAuth/OAuthClient.php

@@ -0,0 +1,126 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Framework\OAuth;
+
+use App\Framework\HttpClient\HttpClient;
+use App\Framework\OAuth\ValueObjects\OAuthToken;
+
+/**
+ * Generic OAuth Client
+ *
+ * Handles HTTP requests to OAuth providers using framework's HttpClient
+ */
+final readonly class OAuthClient
+{
+    public function __construct(
+        private HttpClient $httpClient,
+    ) {}
+
+    /**
+     * Make GET request to OAuth provider
+     *
+     * @param array<string, string> $headers
+     * @return array<string, mixed>
+     */
+    public function get(string $url, OAuthToken $token, array $headers = []): array
+    {
+        $response = $this->httpClient->get($url, [
+            'headers' => [
+                'Authorization' => $token->getAuthorizationHeader(),
+                ...$headers,
+            ],
+        ]);
+
+        return json_decode($response->getBody(), true) ?? [];
+    }
+
+    /**
+     * Make POST request to OAuth provider
+     *
+     * @param array<string, mixed> $data
+     * @param array<string, string> $headers
+     * @return array<string, mixed>
+     */
+    public function post(string $url, array $data = [], array $headers = []): array
+    {
+        $response = $this->httpClient->post($url, [
+            'headers' => [
+                'Content-Type' => 'application/x-www-form-urlencoded',
+                ...$headers,
+            ],
+            'body' => http_build_query($data),
+        ]);
+
+        return json_decode($response->getBody(), true) ?? [];
+    }
+
+    /**
+     * Make authenticated POST request with OAuth token
+     *
+     * @param array<string, mixed> $data
+     * @param array<string, string> $headers
+     * @return array<string, mixed>
+     */
+    public function postAuthenticated(
+        string $url,
+        OAuthToken $token,
+        array $data = [],
+        array $headers = []
+    ): array {
+        $response = $this->httpClient->post($url, [
+            'headers' => [
+                'Authorization' => $token->getAuthorizationHeader(),
+                'Content-Type' => 'application/json',
+                ...$headers,
+            ],
+            'body' => json_encode($data),
+        ]);
+
+        return json_decode($response->getBody(), true) ?? [];
+    }
+
+    /**
+     * Make PUT request with OAuth token
+     *
+     * @param array<string, mixed> $data
+     * @param array<string, string> $headers
+     * @return array<string, mixed>
+     */
+    public function put(
+        string $url,
+        OAuthToken $token,
+        array $data = [],
+        array $headers = []
+    ): array {
+        $response = $this->httpClient->put($url, [
+            'headers' => [
+                'Authorization' => $token->getAuthorizationHeader(),
+                'Content-Type' => 'application/json',
+                ...$headers,
+            ],
+            'body' => json_encode($data),
+        ]);
+
+        return json_decode($response->getBody(), true) ?? [];
+    }
+
+    /**
+     * Make DELETE request with OAuth token
+     *
+     * @param array<string, string> $headers
+     * @return array<string, mixed>
+     */
+    public function delete(string $url, OAuthToken $token, array $headers = []): array
+    {
+        $response = $this->httpClient->delete($url, [
+            'headers' => [
+                'Authorization' => $token->getAuthorizationHeader(),
+                ...$headers,
+            ],
+        ]);
+
+        return json_decode($response->getBody(), true) ?? [];
+    }
+}