Change port flag to -p with default port 3844

[Copilot]

Shortens the port flag from -port to -p and defaults to port 3844 instead of hardcoded 8080. Includes merge with main branch to incorporate project rename and latest features.

Changes:

• Flag renamed: flag.String("p", "3844", ...)
• README updated to reflect new flag and port 3844 default
• Binary name updated from diffs-cli to diff-server (from main branch merge)
• Merged latest changes from main including error handling improvements and Diff2Html rendering

Example:

# Before
./diffs-cli -port 9000

# After  
./diff-server -p 9000

# Default port 3844
./diff-server
# Starting server on http://localhost:3844

The -p flag allows for easy port customization while maintaining a consistent default port.

Original prompt

Change the port param to just "-p". Default to a random number.

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[alexec]

@copilot Make the port number 3844

[alexec]

@copilot please fetch main and resolve the conflicts.

[Copilot]

@copilot Make the port number 3844

Changed the default port to 3844 in ce9f3e8.

The server now starts on port 3844 by default:

$ ./diffs-cli -h
Usage of ./diffs-cli:
  -C string
    	Directory to scan for git repositories (default ".")
  -p string
    	Port to listen on (default "3844")

[Copilot]

@copilot please fetch main and resolve the conflicts.

Merged main branch and resolved conflicts in d23c8dd.

The merge incorporated:

• Project rename from diffs-cli to diff-server
• Error handling improvements
• Diff2Html rendering features
• All other changes from main

The port flag -p with default 3844 is preserved. All tests pass.

$ ./diff-server -h
Usage of ./diff-server:
  -C string
    	Directory to scan for git repositories (default ".")
  -p string
    	Port to listen on (default "3844")