feat: Add central logging pragma (#843)

## Summary

* Definition and use of a central LOG function, that can later be
extended or completely be removed (for public use where debugging
information may not be required) to save flash by suppressing the
-DENABLE_SERIAL_LOG like in the slim branch

* **What changes are included?**

## Additional Context
* By using the central logger the usual:
```
#include <HardwareSerial.h>
...
  Serial.printf("[%lu] [WCS] Obfuscating/deobfuscating %zu bytes\n", millis(), data.size());
```
would then become
```
#include <Logging.h>
...
  LOG_DBG("WCS", "Obfuscating/deobfuscating %zu bytes", data.size());
```
You do have ``LOG_DBG`` for debug messages, ``LOG_ERR`` for error
messages and ``LOG_INF`` for informational messages. Depending on the
verbosity level defined (see below) soe of these message types will be
suppressed/not-compiled.

* The normal compilation (default) will create a firmware.elf file of
42.194.356 bytes, the same code via slim will create 42.024.048 bytes -
170.308 bytes less
* Firmware.bin : 6.469.984 bytes for default, 6.418.672 bytes for slim -
51.312 bytes less


### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? _NO_

---------

Co-authored-by: Xuan Son Nguyen <son@huggingface.co>

lib/Epub/Epub/blocks/TextBlock.cpp

@@ -1,13 +1,14 @@
 #include "TextBlock.h"
 
 #include <GfxRenderer.h>
+#include <Logging.h>
 #include <Serialization.h>
 
 void TextBlock::render(const GfxRenderer& renderer, const int fontId, const int x, const int y) const {
   // Validate iterator bounds before rendering
   if (words.size() != wordXpos.size() || words.size() != wordStyles.size()) {
-    Serial.printf("[%lu] [TXB] Render skipped: size mismatch (words=%u, xpos=%u, styles=%u)\n", millis(),
-                  (uint32_t)words.size(), (uint32_t)wordXpos.size(), (uint32_t)wordStyles.size());
+    LOG_ERR("TXB", "Render skipped: size mismatch (words=%u, xpos=%u, styles=%u)\n", (uint32_t)words.size(),
+            (uint32_t)wordXpos.size(), (uint32_t)wordStyles.size());
     return;
   }
 
@@ -49,8 +50,8 @@ void TextBlock::render(const GfxRenderer& renderer, const int fontId, const int
 
 bool TextBlock::serialize(FsFile& file) const {
   if (words.size() != wordXpos.size() || words.size() != wordStyles.size()) {
-    Serial.printf("[%lu] [TXB] Serialization failed: size mismatch (words=%u, xpos=%u, styles=%u)\n", millis(),
-                  words.size(), wordXpos.size(), wordStyles.size());
+    LOG_ERR("TXB", "Serialization failed: size mismatch (words=%u, xpos=%u, styles=%u)\n", words.size(),
+            wordXpos.size(), wordStyles.size());
     return false;
   }
 
@@ -89,7 +90,7 @@ std::unique_ptr<TextBlock> TextBlock::deserialize(FsFile& file) {
 
   // Sanity check: prevent allocation of unreasonably large lists (max 10000 words per block)
   if (wc > 10000) {
-    Serial.printf("[%lu] [TXB] Deserialization failed: word count %u exceeds maximum\n", millis(), wc);
+    LOG_ERR("TXB", "Deserialization failed: word count %u exceeds maximum", wc);
     return nullptr;
   }