Examples: third party language interop

[leshy]

had to recreate the PR, rewrote simplerobot.py and adressed other comments

[greptile-apps]

Greptile Summary

This PR adds comprehensive third-party language interoperability examples demonstrating how to control dimos robots from C++, Lua, TypeScript, and web browsers via LCM messaging.

Key Changes:

• Fixed In.transport setter in dimos/core/stream.py to actually assign the transport (was previously a no-op)
• Completely rewrote simplerobot.py as a proper Module with reactive streams, unicycle physics model, pygame visualization, and self-test mode
• Added working examples in C++ (with CMake), Lua (with setup script), TypeScript/Deno (CLI and web UI)
• Created WebSocket bridge (ts/web/server.ts) that forwards raw LCM packets between browsers and UDP, enabling browser-based robot control with direct LCM encoding/decoding
• Disabled debug logging in Foxglove bridge for cleaner output

Issue Found:

• Physics bug in simplerobot.py:41-42 where position integration uses old yaw instead of newly calculated yaw after angular velocity is applied, causing incorrect trajectory calculation

Confidence Score: 4/5

• Safe to merge after fixing the physics bug in apply_twist function
• The PR adds valuable functionality with well-structured examples across multiple languages. The core transport setter fix is correct and important. However, there's a logical error in the unicycle model physics that will cause incorrect robot motion - the position update uses the old yaw angle instead of the updated one. Once fixed, this PR significantly improves the project's language interoperability.
• examples/simplerobot/simplerobot.py requires fix to the physics calculation before merge

Important Files Changed

Filename	Overview
dimos/core/stream.py	Fixed transport setter in In class to actually assign value instead of no-op
examples/simplerobot/simplerobot.py	Complete rewrite of SimpleRobot as a proper Module with In/Out streams, unicycle physics model, self-test mode
examples/simplerobot/vis.py	New pygame-based visualization showing robot position, heading, velocity with grid overlay
examples/language-interop/cpp/main.cpp	C++ example subscribing to /odom and publishing sinusoidal twist commands to /cmd_vel
examples/language-interop/lua/main.lua	Lua example with LCM bindings subscribing to pose and publishing twist commands
examples/language-interop/ts/main.ts	TypeScript/Deno example demonstrating LCM pub/sub with robot control
examples/language-interop/ts/web/server.ts	WebSocket bridge forwarding LCM packets between browser and UDP for browser-based robot control

Sequence Diagram

sequenceDiagram
    participant User as User/Browser
    participant CPP as C++ Client
    participant LUA as Lua Client
    participant TS as TypeScript Client
    participant WS as WebSocket Bridge
    participant LCM as LCM (UDP)
    participant Robot as SimpleRobot

    Note over Robot: SimpleRobot Module starts
    Robot->>LCM: Setup transport on /odom
    Robot->>LCM: Setup transport on /cmd_vel
    Robot->>Robot: Start update loop (30Hz)

    Note over Robot: Publish pose every 33ms
    loop Every 33ms
        Robot->>LCM: Publish PoseStamped to /odom
    end

    Note over CPP,TS: External clients can control robot

    alt C++ Client
        CPP->>LCM: Subscribe to /odom
        LCM->>CPP: Receive PoseStamped
        CPP->>LCM: Publish Twist to /cmd_vel
        LCM->>Robot: Receive Twist command
        Robot->>Robot: Update velocity & pose
    end

    alt Lua Client
        LUA->>LCM: Subscribe to /odom
        LCM->>LUA: Receive PoseStamped
        LUA->>LCM: Publish Twist to /cmd_vel
        LCM->>Robot: Receive Twist command
        Robot->>Robot: Update velocity & pose
    end

    alt TypeScript Client
        TS->>LCM: Subscribe to /odom
        LCM->>TS: Receive PoseStamped
        TS->>LCM: Publish Twist to /cmd_vel
        LCM->>Robot: Receive Twist command
        Robot->>Robot: Update velocity & pose
    end

    alt Browser Client
        User->>WS: Connect WebSocket
        WS->>LCM: Subscribe to all packets
        LCM->>WS: Forward PoseStamped packet
        WS->>User: Send binary LCM packet
        User->>User: Decode in browser
        User->>WS: Send Twist (encoded LCM)
        WS->>LCM: Forward packet to UDP
        LCM->>Robot: Receive Twist command
        Robot->>Robot: Update velocity & pose
    end

    Note over Robot: Apply unicycle physics
    Robot->>Robot: Integrate velocity commands
    Robot->>Robot: Timeout check (0.5s)

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