Added a (rough) roadmap to resolving a number of known issues

server/pairing/TODO.MD

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+# Local Pairing To-dos
+
+- [Network Address / Peer Discovery](#network-address--peer-discovery)
+- [Network Debug Diagnostics](#network-debug-diagnostics)
+
+## Network Address / Peer Discovery
+
+Revamp the preferred network discovery process
+
+Note this functionality is pre-secret share so doesn't ...
+
+- **Pre-shared secret: scan the QR code first, containing the secret and then attempt to discover the other device(s)**
+  - ⚠️ **Problem:** Only works if UDP discovery works. [See possible solution for UDP discovery failure mitigation](#udp-discovery-failure-mitigation)
+  - Start pairing server on relevant device, listen to `0.0.0.0`.
+    - get selected port number
+    - get TLS pub key
+    - get secret
+  - Scan QR code which including:
+    - selected port number
+    - TLS pub key
+    - secret
+  - UDP discovery happens 🧙🪄✨
+  - devices acquire ip addresses of peer(s), and themselves.
+  - client device attempts connection as normal
+- **Post-shared secret, which is confirmed later with the QR code**
+  - UDP discovery happens 🧙🪄✨
+  - devices acquire ip addresses of peer(s), and themselves.
+    - can also optionally give feedback to the user with the pairing options.
+  - server device starts server listener, listen to known network ip address
+    - get selected port number
+    - get TLS pub key
+    - get secret
+  - Scan QR code which including:
+    - selected port number
+    - TLS pub key
+    - secret
+  - client device attempts connection as normal
+
+### Self IP address acquisition
+
+1. Ask network interface for its preferred outbound IP address
+    - The process currently relied on
+    - Add a required a self "confirmation" ping, to ensure the given address is network addressable.
+    - On fail, fall through to stage 2
+2. device gets a list of its network addresses.
+   - Use `netIfaces, err := net.Interfaces()` [See snippet](#get-all-network-addresses)
+   - run filter for only local private net addrs
+   - open listener on 0.0.0.0
+   - make an outbound network call to all ips
+      - call should include the addressing ip so device knows which address is network addressable
+   - record all ip addresses that are able to ping the listener.
+      - hopefully the list will only ever contain 1 IP address
+   - On fail, fall through to stage 3
+3. Attempt discovery via UDP multicast
+    - **Question :** How do **both** devices know when to start UDP discovery?
+      - Perhaps the QR code device can add details to the application
+    - no guarantee that both devices get an IP address
+      - [See UDP discovery failure mitigation](#udp-discovery-failure-mitigation)
+
+## Network Debug Diagnostics
+
+We need to check a few things if a connection isn't working
+
+- What network ip address does the device think it has?
+- What is the port number the listener is listening on?
+- Can the device access its own network IP address?
+- Can a device find, and be found by, other devices?
+  - attempt UDP discovery
+- What is the device's network connection(s) status?
+  - `ipconfig` / `ifconfig`
+- Test each in series, all above functions
+  - Capture everything, even errors
+    - DO NOT early return errors, log the errors, proceed with the next function.
+  - log all outputs to standard logger
+  - log all outputs memory for export / return
+  - When test suite is complete return log out put
+
+## Refs
+
+###### UDP discovery failure mitigation
+
+ - Both devices listen on a tcp port chosen by the network interface
+ - Attempt UDP discovery
+ - In the UDP packet include:
+   - the device's listener port number
+   - ensure the notifier's id is stored for later connections via tcp
+ - When peer A discovers peer B, peer A pings peer B's "confirmation" listener with peer B's IP address and network info about peer A
+ - peer B attempts an outbound **TLS** connection to its own "confirmation" server, with a random code, to confirm its own IP address.
+
+
+###### Get all network addresses
+
+```go
+package test
+
+import (
+   "fmt"
+   "net"
+)
+
+func AllNetworkAddresses() error {
+   netIfaces, err := net.Interfaces()
+   if err != nil {
+      return err
+   }
+
+   for _, i := range netIfaces {
+      addrs, err := i.Addrs()
+      if err != nil {
+         return err
+      }
+
+      for _, addr := range addrs {
+         var ip net.IP
+         switch v := addr.(type) {
+         case *net.IPNet:
+            ip = v.IP
+         case *net.IPAddr:
+            ip = v.IP
+         default:
+			 return fmt.Errorf("unknown ip type %s", v)
+         }
+         fmt.Print(ip)
+      }
+   }
+   return nil
+}
+```