Misc design-question TODOs worth a look (fixed capacities, stale comment, eviction edge case)

[davidchatting-bot]

A grab-bag of smaller `TODO` comments in `src/` that don't warrant their own issue individually but are worth a punch-list:

• `YoYoWiFiManager.h:98` - `StaticJsonDocument<8192> broadcastMessageList; //TODO: this should be dynamic?` - fixed 8KB capacity for the queue of messages waiting to be broadcast to peers; worth deciding if that's enough headroom or should be a `DynamicJsonDocument`.
• `YoYoWiFiManager.cpp`, `onYoYoRequestPOST()`/dead code in `onYoYoRequestDELETE()` - `//TODO: this limit seems artificial` (x2) - the 1024-byte fixed buffer for incoming JSON POST/DELETE bodies; worth deciding if that's an intentional ceiling (memory-constrained device) or should be configurable/dynamic.
• `YoYoWiFiManager.cpp`, `onYoYoMessagePOST()` - `request->send(200, "application/javascript", getCredentialsAsJsonString()); //TODO: is this the problem?` - looks like a leftover debugging note from investigating what's now closed issue POSTing to /yoyo/credentials does not return a code #16; worth confirming it's no longer suspect and removing the comment.
• `YoYoWiFiManager.cpp`, `getCredentialsAsJsonString()` - `serializeJson(jsonDoc, jsonString); //TODO: test length` - unlike the fixed `char*` buffers elsewhere (see Heap buffer overflow: unbounded strcpy of untrusted JSON in setCredentials() #56/Unbounded strcpy(response, ...) in POST()/GET() HTTP client helpers #68), this serializes into a `String`, so it's not an overflow risk, just worth confirming there's no practical size ceiling worth handling.
• `YoYoWiFiManager.cpp`, `getCredentialsAsJson()` - `//TODO: should in same structure - just missing the password field or replacing with s` - a design comment about whether starring-out passwords (`***`) vs. omitting the `password` field entirely is the better shape for `GET /yoyo/credentials`'s response.
• `YoYoSettings.h:53` - `while(force && isFull()) removeNetwork(0, false); //...TODO: should it delete this network if lastnetwork is set true?` - when storage is full, the oldest network (index 0) is evicted to make room for a new one; open question of whether it should skip/protect the network currently flagged `lastnetwork` (the one actively in use) from eviction.
• `YoYoWiFiManager/wifi_sta.h:4` - `#define ESP_WIFI_MAX_CONN_NUM (10) //TODO: is this right? This is the max for ESP32` - this constant is used in the ESP8266 branch of `updateClientList()` but the comment notes it's actually the ESP32 max; worth confirming the correct ESP8266 station limit and using that instead.

None of these are known-broken today as far as I've found - more a list of open design questions/cleanup left by the original TODOs, grouped here rather than as one-line issues each.