Refactor and update various components of EchoHub.Server

- Updated launchSettings.json for consistency.
- Refactored FileValidationHelper to improve image validation logic.
- Enhanced ServerDirectoryService for better connection handling and user count updates.
- Improved DatabaseSetup for legacy database handling and seeding default channels.
- Refined FirstRunSetup to ensure JWT secret generation.
- Removed appsettings.Development.json as it is no longer needed.
- Updated EchoHub.Tests project file for consistency.
- Added unit tests for FileValidationHelper and PresenceTracker with improved assertions.
- Updated ValidationConstantsTests to ensure regex validations are correct.
- Cleaned up solution file formatting for better readability.

CONTRIBUTING.md

@@ -1,101 +1,101 @@
-# Contributing to EchoHub
-
-Thanks for your interest in contributing — EchoHub aims to stay lightweight, terminal-first, and self-hosted.
-
-## Quick start (dev)
-
-### Prerequisites
-
-- .NET 10 SDK
-
-### Build
-
-```bash
-dotnet build src/EchoHub.slnx
-```
-
-### Test
-
-```bash
-dotnet test src/EchoHub.slnx
-```
-
-### Run (local)
-
-Server:
-
-```bash
-dotnet run --project src/EchoHub.Server
-```
-
-Client:
-
-```bash
-dotnet run --project src/EchoHub.Client
-```
-
-## What to work on
-
-- Check open issues (especially `good first issue` / `help wanted` if present)
-- Docs fixes in `docs/` are always welcome
-- Tests: `src/EchoHub.Tests/`
-
-If you’re proposing a larger change, open an issue first so we can align on approach.
-
-## Code style & expectations
-
-- Keep PRs focused (small and reviewable)
-- Prefer clear naming over cleverness
-- Add/adjust tests for bug fixes when it’s practical
-- Avoid committing secrets (JWT secrets, tokens, connection strings)
-
-## Docs
-
-This repo uses DocFX for the site in `docs/`.
-
-To build docs locally you typically need the assemblies built in Release first:
-
-```bash
-dotnet build src/EchoHub.slnx --configuration Release
-```
-
-Then run DocFX:
-
-```bash
-docfx docs/docfx.json
-```
-
-## Markdown lint
-
-CI lints Markdown. Locally:
-
-- On Linux/macOS (or Windows with Git Bash/WSL):
-
-```bash
-./scripts/lint-markdown.sh
-```
-
-- Anywhere with Node.js installed:
-
-```bash
-npx --yes markdownlint-cli2
-```
-
-## Pull requests
-
-- Fill out the PR template
-- Ensure `dotnet test src/EchoHub.slnx` is green
-- Mention any behavioral changes (client UX, auth, uploads)
-
-## Commit messages
-
-Any consistent style is fine; descriptive subjects help reviews.
-Examples:
-
-- `fix(server): validate image magic bytes`
-- `feat(client): add /servers improvements`
-- `docs: clarify getting started`
-
-## Reporting security issues
-
-Please do **not** file public issues for security problems. See `SECURITY.md`.
+# Contributing to EchoHub
+
+Thanks for your interest in contributing — EchoHub aims to stay lightweight, terminal-first, and self-hosted.
+
+## Quick start (dev)
+
+### Prerequisites
+
+- .NET 10 SDK
+
+### Build
+
+```bash
+dotnet build src/EchoHub.slnx
+```
+
+### Test
+
+```bash
+dotnet test src/EchoHub.slnx
+```
+
+### Run (local)
+
+Server:
+
+```bash
+dotnet run --project src/EchoHub.Server
+```
+
+Client:
+
+```bash
+dotnet run --project src/EchoHub.Client
+```
+
+## What to work on
+
+- Check open issues (especially `good first issue` / `help wanted` if present)
+- Docs fixes in `docs/` are always welcome
+- Tests: `src/EchoHub.Tests/`
+
+If you’re proposing a larger change, open an issue first so we can align on approach.
+
+## Code style & expectations
+
+- Keep PRs focused (small and reviewable)
+- Prefer clear naming over cleverness
+- Add/adjust tests for bug fixes when it’s practical
+- Avoid committing secrets (JWT secrets, tokens, connection strings)
+
+## Docs
+
+This repo uses DocFX for the site in `docs/`.
+
+To build docs locally you typically need the assemblies built in Release first:
+
+```bash
+dotnet build src/EchoHub.slnx --configuration Release
+```
+
+Then run DocFX:
+
+```bash
+docfx docs/docfx.json
+```
+
+## Markdown lint
+
+CI lints Markdown. Locally:
+
+- On Linux/macOS (or Windows with Git Bash/WSL):
+
+```bash
+./scripts/lint-markdown.sh
+```
+
+- Anywhere with Node.js installed:
+
+```bash
+npx --yes markdownlint-cli2
+```
+
+## Pull requests
+
+- Fill out the PR template
+- Ensure `dotnet test src/EchoHub.slnx` is green
+- Mention any behavioral changes (client UX, auth, uploads)
+
+## Commit messages
+
+Any consistent style is fine; descriptive subjects help reviews.
+Examples:
+
+- `fix(server): validate image magic bytes`
+- `feat(client): add /servers improvements`
+- `docs: clarify getting started`
+
+## Reporting security issues
+
+Please do **not** file public issues for security problems. See `SECURITY.md`.