File locking and DevelopmentService improvements (#358)

- Moved `file::getlock(path)` from `Tactility` to `TactilityCore`
- Changed all existing `file::*` functions to implement locking by default
- Removed all manual locking where `file::*` functions were used
- When `DevelopmentService` receives a file, it doesn't try to allocate it all in memory. This fixes going out-of-memory on devices without PSRAM.
- Fix for TactilityC include

Tactility/Include/Tactility/file/FileLock.h

@@ -13,20 +13,8 @@ namespace tt::file {
 
 /**
  * @param[in] path the path to find a lock for
- * @return a non-null lock for the specified path.
+ * @return a lock instance when a lock was found, otherwise nullptr
  */
-std::shared_ptr<Lock> getLock(const std::string& path);
-
-/**
- * Acquires a lock, calls the function, then releases the lock.
- * @param[in] path the path to find a lock for
- * @param[in] fn the code to execute while the lock is acquired
- */
-template<typename ReturnType>
-ReturnType withLock(const std::string& path, std::function<ReturnType()> fn) {
-    const auto lock = getLock(path)->asScopedLock();
-    lock.lock();
-    return fn();
-}
+std::shared_ptr<Lock> _Nullable findLock(const std::string& path);
 
 }

Tactility/Include/Tactility/network/HttpdReq.h

@@ -24,6 +24,8 @@ std::map<std::string, std::string> parseContentDisposition(const std::vector<std
 
 bool readAndDiscardOrSendError(httpd_req_t* request, const std::string& toRead);
 
+size_t receiveFile(httpd_req_t* request, size_t length, const std::string& filePath);
+
 }
 
 #endif // ESP_PLATFORM