deprecate(lmxproxy): move all LmxProxy code, tests, and docs to deprecated/

LmxProxy is no longer needed. Moved the entire lmxproxy/ workspace, DCL
adapter files, and related docs to deprecated/. Removed LmxProxy registration
from DataConnectionFactory, project reference from DCL, protocol option from
UI, and cleaned up all requirement docs.

deprecated/lmxproxy/docs/requirements/Component-SessionManager.md

@@ -0,0 +1,76 @@
+# Component: SessionManager
+
+## Purpose
+
+Tracks active client sessions, mapping session IDs to client metadata. Provides session creation, validation, and termination for the gRPC service layer.
+
+## Location
+
+`src/ZB.MOM.WW.LmxProxy.Host/Sessions/SessionManager.cs`
+
+## Responsibilities
+
+- Create new sessions with unique identifiers when clients connect.
+- Validate session IDs on every data operation.
+- Track session metadata (client ID, API key, connection time, last activity).
+- Terminate sessions on client disconnect.
+- Provide session listing for monitoring and status reporting.
+
+## 1. Session Storage
+
+- Sessions are stored in a `ConcurrentDictionary<string, SessionInfo>` (lock-free, thread-safe).
+- Session state is in-memory only — all sessions are lost on service restart.
+- `ActiveSessionCount` property returns the current count of tracked sessions.
+
+## 2. Session Lifecycle
+
+### 2.1 Creation
+
+`CreateSession(clientId, apiKey)`:
+- Generates a unique session ID: `Guid.NewGuid().ToString("N")` (32-character lowercase hex string, no hyphens).
+- Creates a `SessionInfo` record with `ConnectedAt` and `LastActivity` set to `DateTime.UtcNow`.
+- Stores the session in the dictionary.
+- Returns the session ID to the client.
+
+### 2.2 Validation
+
+`ValidateSession(sessionId)`:
+- Looks up the session ID in the dictionary.
+- If found, updates `LastActivity` to `DateTime.UtcNow` and returns `true`.
+- If not found, returns `false`.
+
+### 2.3 Termination
+
+`TerminateSession(sessionId)`:
+- Removes the session from the dictionary.
+- Returns `true` if the session existed, `false` otherwise.
+
+### 2.4 Query
+
+- `GetSession(sessionId)` — Returns `SessionInfo` or `null` if not found.
+- `GetAllSessions()` — Returns `IReadOnlyList<SessionInfo>` snapshot of all active sessions.
+
+## 3. SessionInfo
+
+| Field | Type | Description |
+|-------|------|-------------|
+| SessionId | string | 32-character hex GUID |
+| ClientId | string | Client-provided identifier |
+| ApiKey | string | API key used for authentication |
+| ConnectedAt | DateTime | UTC time of session creation |
+| LastActivity | DateTime | UTC time of last operation (updated on each validation) |
+| ConnectedSinceUtcTicks | long | `ConnectedAt.Ticks` for gRPC response serialization |
+
+## 4. Disposal
+
+`Dispose()` clears all sessions from the dictionary. No notifications are sent to connected clients.
+
+## Dependencies
+
+None. SessionManager is a standalone in-memory store with no external dependencies.
+
+## Interactions
+
+- **GrpcServer** calls `CreateSession` on Connect, `ValidateSession` on every data operation, and `TerminateSession` on Disconnect.
+- **HealthAndMetrics** reads `ActiveSessionCount` for health check data.
+- **StatusReportService** reads session information for the status dashboard.